| the amino acid sequence of the trimethoprim-resistant dihydrofolate reductase specified in escherichia coli by r-plasmid r67. | the amino acid sequence of a trimethoprim-resistant dihydrofolate reductase (ec 1.5.1.3) specified by the r-plasmid r67 is described. the sequence was deduced from automatic and manual sequence analysis of the intact protein, the fragments produced by cyanogen bromide cleavage, and peptides derived from the largest cyanogen bromide fragment by digestion with trypsin, staphylococcus aureus v8 proteus, chymotrypsin, and lysobacter enzymogenes alpha-lytic protease. the complete sequence comprises 7 ... | 1979 | 387758 |
| the complete amino acid sequence of the major kunitz trypsin inhibitor from the seeds of prosopsis juliflora. | the major inhibitor of trypsin in seeds of prosopsis juliflora was purified by precipitation with ammonium sulphate, ion-exchange column chromatography on deae- and cm-sepharose and preparative reverse phase hplc on a vydac c-18 column. the protein inhibited trypsin in the stoichiometric ratio of 1:1, but had only weak activity against chymotrypsin and did not inhibit human salivary or porcine pancreatic alpha-amylases. sds-page indicated that the inhibitor has a mr of ca 20,000, and ief-page sh ... | 1991 | 1367792 |
| correct folding of alpha-lytic protease is required for its extracellular secretion from escherichia coli. | alpha-lytic protease is a bacterial serine protease of the trypsin family that is synthesized as a 39-kd preproenzyme (silen, j. l., c. n. mcgrath, k. r. smith, and d. a. agard. 1988. gene (amst.). 69: 237-244). the 198-amino acid mature protease is secreted into the culture medium by the native host, lysobacter enzymogenes (whitaker, d. r. 1970. methods enzymol. 19:599-613). expression experiments in escherichia coli revealed that the 166-amino acid pro region is transiently required either in ... | 1992 | 1618906 |
| characterization of rarobacter faecitabidus protease i, a yeast-lytic serine protease having mannose-binding activity. | rarobacter faecitabidus protease i, a yeast-lytic serine protease, was characterized in order to elucidate the mechanism of lysis of yeast cells by this enzyme. the n-terminal amino acid sequence of the enzyme was found to be homologous to those of lysobacter enzymogenes alpha-lytic protease and streptomyces griseus proteases a and b around the catalytic his residue, showing that it is a mammalian type serine protease. in a study of its substrate specificity, it preferentially hydrolyzed the est ... | 1991 | 1778983 |
| nucleotide sequence and characterization of the gene for secreted alkaline phosphatase from lysobacter enzymogenes. | lysobacter enzymogenes produces an alkaline phosphatase which is secreted into the medium. the gene for the enzyme (phoa) was isolated from a recombinant lambda library. it was identified within a 4.4-kb ecori-bamh1 fragment, and its sequence was determined by the chain termination method. the structural gene consists of an open reading frame which encodes a 539-amino-acid protein with a 29-residue signal sequence, followed by a 119-residue propeptide, the 281-residue mature phosphatase, and a 1 ... | 1991 | 1856159 |
| beta-lactamase of lysobacter enzymogenes: induction, purification and characterization. | lysobacter enzymogenes produces an inducible beta-lactamase and induction with 100 micrograms ampicillin ml-1 resulted in an increase of more than 100-fold in enzyme activity. various other beta-lactam antibiotics also served as effective inducers. the enzyme was obtained from cells by osmotic shocking to release periplasmic components and it was purified primarily by ion-exchange chromatography and page. the beta-lactamase consists of one polypeptide with a molecular mass of about 28 kda and an ... | 1990 | 2118167 |
| molecular cloning and nucleotide sequence of the beta-lytic protease gene from achromobacter lyticus. | two bacteriolytic enzymes secreted by achromobacter lyticus m497-1 were purified and identified as being very similar (considering their amino acid composition and n-terminal sequence) to alpha- and beta-lytic proteases from lysobacter enzymogenes. a 1.8-kb ecori fragment containing the structural gene for beta-lytic protease was cloned from a. lyticus chromosomal dna. the protein sequence deduced from the nucleotide sequence was identical to the known sequence of beta-lytic protease, except for ... | 1990 | 2228973 |
| the use of tween 20 in a sensitive turbidimetric assay of lipolytic enzymes. | a turbidimetric esterase assay was developed using a tween 20 solution in the presence of cacl2 and lysobacter enzymogenes esterase (ec 3.1.1.1) as the enzyme source. the reaction was followed by measuring the increase in the optical density at 500 nm (od500) due to the hydrolytic release of the fatty acids from tween 20 and their precipitation as the calcium salts. concentrations of 1.8% tween and 3 mm cacl2 were found to be optimal for the assay of 0.036 to 0.15 esterase units in a 4-ml reacti ... | 1989 | 2501015 |
| the alpha-lytic protease pro-region does not require a physical linkage to activate the protease domain in vivo. | alpha-lytic protease, an extracellular serine protease of lysobacter enzymogenes 495, is synthesized as a pre-pro-protein. previously it has been shown that when expressed in escherichia coli, the protein is autocatalytically processed in the periplasmic space, and that the functional protease domain accumulates extracellularly. engineered proteins lacking the 166 amino-acid pro-region were enzymatically inactive and remained cell-associated. by independently expressing the pro- and protease dom ... | 1989 | 2507926 |
| structural analysis of specificity: alpha-lytic protease complexes with analogues of reaction intermediates. | to better understand the structural basis of enzyme specificity, the structures of complexes formed between alpha-lytic protease, an extracellular serine protease of lysobacter enzymogenes, and five inhibitory peptide boronic acids (r2-borox, where r2 is methoxysuccinyl-ala-ala-pro- and borox is the alpha-aminoboronic acid analogue of ala, val, ile, norleu, or phe) have been studied at high resolution by x-ray crystallography. the enzyme has primary specificity for ala in the p1 position of pept ... | 1989 | 2611204 |
| analysis of prepro-alpha-lytic protease expression in escherichia coli reveals that the pro region is required for activity. | the alpha-lytic protease of lysobacter enzymogenes was successfully expressed in escherichia coli by fusing the promoter and signal sequence of the e. coli phoa gene to the proenzyme portion of the alpha-lytic protease gene. following induction, active enzyme was found both within cells and in the extracellular medium, where it slowly accumulated to high levels. use of a similar gene fusion to express the protease domain alone produced inactive enzyme, indicating that the large amino-terminal pr ... | 1989 | 2646278 |
| an immunologically related family of apolipoproteins associated with triacylglycerol storage in the cruciferae. | the major apolipoproteins associated with oil-storage bodies have been isolated from the mature seeds of six different species of the family cruciferae. the apolipoproteins were all of molecular mass 19-20 kda. they were highly abundant in mature seed tissue, accounting for up to 20% total seed proteins, and were localized exclusively on the membranes of oil-storage bodies. antibodies were raised in rabbits and mice against the six purified apolipoproteins. in each case, the antibodies specifica ... | 1989 | 2774566 |
| comparison of the phosphatases of lysobacter enzymogenes with those of related bacteria. | lysobacter enzymogenes atcc 29487 (uasm 495) produces an outer-membrane-associated phosphatase and an excreted phosphatase. the cell-associated enzyme was compared to phosphatases of nine other gram-negative gliding bacteria and to that of escherichia coli. the other three species of the genus lysobacter also produce a particulate, cell-associated phosphatase. antiserum prepared against the phosphatase from the outer membrane of l. enzymogenes effectively precipitated the phosphatases of two oth ... | 1987 | 2833562 |
| evolution of the regulatory isozymes of 3-deoxy-d-arabino-heptulosonate 7-phosphate synthase present in the escherichia coli genealogy. | the evolutionary history of isozymes for 3-deoxy-d-arabino-heptulosonate 7-phosphate (dahp) synthase has been constructed in a phylogenetic cluster of procaryotes (superfamily b) that includes escherichia coli. members of superfamily b that have been positioned on a phylogenetic tree by oligonucleotide cataloging possess one or more of four distinct isozymes of dahp synthase. dahp synthase-0 is insensitive to feedback inhibition, while dahp synthase-tyr, dahp synthase-trp, and dahp synthase-phe ... | 1986 | 2867085 |
| the alpha-lytic protease gene of lysobacter enzymogenes. the nucleotide sequence predicts a large prepro-peptide with homology to pro-peptides of other chymotrypsin-like enzymes. | alpha-lytic protease is a 19.8-kda protein secreted from the gram-negative bacterium lysobacter enzymogenes. we have cloned and sequenced the gene for this serine protease. the nucleotide sequence contains an open reading frame which codes for the 198-residue mature enzyme and a potential prepro-peptide, also of 198 residues. the cooh-terminal 49 residues of the pro-peptide are significantly homologous to the propeptides of streptomyces griseus proteases a and b. we suggest that this pro-peptide ... | 1988 | 3053694 |
| serine protease mechanism: structure of an inhibitory complex of alpha-lytic protease and a tightly bound peptide boronic acid. | the structure of the complex formed between alpha-lytic protease, a serine protease secreted by lysobacter enzymogenes, and n-tert-butyloxycarbonylalanylprolylvaline boronic acid (ki = 0.35 nm) has been studied by x-ray crystallography to a resolution of 2.0 a. the active-site serine forms a covalent, nearly tetrahedral adduct with the boronic acid moiety of the inhibitor. the complex is stabilized by seven hydrogen bonds between the enzyme and inhibitor with additional stabilization arising fro ... | 1987 | 3122831 |
| molecular analysis of the gene encoding alpha-lytic protease: evidence for a preproenzyme. | a 1.7-kb ecori fragment containing the structural gene for alpha-lytic protease has been cloned from lysobacter enzymogenes 495 chromosomal dna: the first example of a gene cloned from this organism. the protein sequence deduced from the nucleotide sequence encoding this serine protease matches the published amino acid sequence [olson et al., nature 228 (1970) 438-442] precisely. sequence analysis and s1 mapping indicate that, like subtilisin [e.g., wells et al., nucleic acids res. 11 (1983) 791 ... | 1988 | 3234766 |
| refined structure of alpha-lytic protease at 1.7 a resolution. analysis of hydrogen bonding and solvent structure. | the structure of alpha-lytic protease, a serine protease produced by the bacterium lysobacter enzymogenes, has been refined at 1.7 a resolution. the conventional r-factor is 0.131 for the 14,996 reflections between 8 and 1.7 a resolution with i greater than or equal to 2 sigma (i). the model consists of 1391 protein atoms, two sulfate ions and 156 water molecules. the overall root-meansquare error is estimated to be about 0.14 a. the refined structure was compared with homologous enzymes alpha-c ... | 1985 | 3900416 |
| distribution of multicopy single-stranded dna among myxobacteria and related species. | multicopy single-stranded dna (msdna) is a short single-stranded linear dna originally discovered in myxococcus xanthus and subsequently found in stigmatella aurantiaca. it exists at an estimated 500 to 700 copies per chromosome (t. yee, t. furuichi, s. inouye, and m. inouye, cell 38:203-209, 1984). we found msdna in other myxobacteria, including myxococcus coralloides, cystobacter violaceus, cystobacter ferrugineus (cbfe17), nannocystis exedens, and nine independently isolated strains of m. xan ... | 1985 | 3932332 |
| extracellular nucleases of lysobacter enzymogenes: production of the enzymes and purification and characterization of an endonuclease. | lysobacter enzymogenes produced a nonspecific extracellular nuclease and an extracellular rnaase when grown in tryptone broth. both enzyme activities appeared after the exponential growth phase of the organism. the addition of rna to the medium specifically inhibited the production of the nuclease and the addition of phosphate prevented the synthesis of the rnaase. dna had no effect on the enzyme production. the lysobacter nuclease was purified 274-fold and its molecular weight was estimated to ... | 1980 | 6257361 |
| unusual sulfonolipids are characteristic of the cytophaga-flexibacter group. | capnocytophaga spp. contain a group of unusual sulfonolipids, called capnoids (w. godchaux iii and e. r. leadbetter, j. bacteriol. 144:592-602, 1980). one of these lipids, capnine, is 2-amino-3-hydroxy-15-methylhexadecane-1-sulfonic acid; the others are, apparently, n-acylated versions of capnine. the lipids were found, in amounts ranging from 2.5 to 16 mumol of capnoid sulfur per g of cells (wet weight), in two cytophaga spp. and also in several closely related organisms: several capnocytophaga ... | 1983 | 6298180 |
| structure of mouse submaxillary gland renin. | to determine the structural basis for the highly specific action of renin, structural features of the active site and the complete amino acid sequence of mouse submaxillary gland renin were determined. a rapid method was developed for a large scale purification of renin from mouse submaxillary gland. the active site of renin was shown to consist of 2 aspartyl residues, 2 tyrosyl residues and one arginyl residue, the structures analogous to the active site of pepsin and other acid proteases. reni ... | 1983 | 6357566 |
| use of endoproteinase lys-c from lysobacter enzymogenes in protein sequence analysis. | endoproteinase lys-c from lysobacter enzymogenes, which is commercially available, proved to be useful in the determination of primary structures of proteins. the enzyme preferentially cleaves at the carboxyl side of lysine residues. | 1983 | 6359954 |
| p-hydroxybenzoate hydroxylase from pseudomonas fluorescens. 1. completion of the elucidation of the primary structure. | as a final step in the elucidation of the primary structure of p-hydroxybenzoate hydroxylase from pseudomonas fluorescens, the amino acid sequences of a cnbr peptide (cb1, positions 111-276), that accounts for the middle part of the sequence, and the c-terminal cnbr peptide (cb2, positions 277-394) from the enzyme were determined. important sequence information was obtained from two subfragments that were formed by the cleavage with cnbr of the met-thr sequence (positions 346-347) in peptide cb2 ... | 1983 | 6406229 |
| production of two phosphatases by lysobacter enzymogenes and purification and characterization of the extracellular enzyme. | lysobacter enzymogenes produces an extracellular phosphatase (ec. 3.1.3.1) during the stationary phase of growth. the cells also produce a cell-associated alkaline phosphatase. this enzyme is found in the particulate fraction of cell extracts and may be membrane bound. the production of both phosphatases, especially the extracellular enzyme, is reduced by inorganic phosphate. the extracellular phosphatase was purified to a specific activity of 270 u/mg primarily by chromatography on carboxymethy ... | 1984 | 6426386 |
| catalytic mechanism of serine proteases: reexamination of the ph dependence of the histidyl 1j13c2-h coupling constant in the catalytic triad of alpha-lytic protease. | l-histidine, 90% 13c enriched at the c2 position, was incorporated into the catalytic triad of alpha-lytic protease (ec 3.4.21.12) with the aid of histidine-requiring mutant of lysobacter enzymogenes (atc 29487), and the ph dependence of the coupling constant between this carbon atom and its directly bonded proton was reinvestigated. the high degree of specific 13c isotopic enrichment attainable with the auxotroph permits direct observation and measurement of this coupling constant in proton-cou ... | 1981 | 7038675 |
| isolation and characterization of the plasma membrane and the outer membrane of deinococcus radiodurans strain sark. | deinococcus radiodurans strain sark, although gram-positive, has a complex cell wall profile that includes an outer membrane-like structure. the outer cell envelope layers formed blebs throughout the growth cycle, which were shed as large vesicles (0.5-3.5 micron m in diameter) from approximately 5% of the cell population. instability was accentuated by treatment with 10% nacl, which released the outer membrane from all cells without disrupting the peptidoglycan layer, and provided an outer memb ... | 1981 | 7296407 |
| protease evolution in streptomyces griseus. discovery of a novel dimeric enzymes. | this report describes the cloning and sequencing of a novel protease gene derived from streptomyces griseus. also described is the heterologous expression of the gene in bacillus subtilis and characterization of the gene product. the sprd gene encodes a prepro mature protease of 392 amino acids tentatively named s. griseus protease d (sgpd). a significant component of the enzyme preregion was found to be homologous with the mitochondrial import signal of hsp60. the sprd gene was subcloned into a ... | 1995 | 7706307 |
| purification and characterization of alkaline serine protease from an alkalophilic streptomyces sp. | sap, an extracellular alkaline serine protease produced by streptomyces sp. ysa-130, was purified to homogeneity by cm-sephadex column chromatography and crystallization. the enzyme was a monomeric protein with a molecular weight of 19,000 as estimated by sds-page and gel filtration. the amino acid composition and amino-terminal sequence of sap were similar to those of other bacterial serine proteases, i.e., streptomyces griseus proteases a and b, lysobacter enzymogenes alpha-lytic protease and ... | 1994 | 7764689 |
| characterization of the gene encoding the glutamic-acid-specific protease of streptomyces griseus. | the complete gene sequence (spre) for the glutamic-acid-specific serine protease (sgpe) of the gram-positive bacterium streptomyces griseus is reported. the spre gene encodes a 355 amino acid pre-pro-mature enzyme. the presence of a glutamic acid residue at the junction of the pro and mature segments of the protein suggests that the enzyme is self-processing. sgpe was found to have extensive homology with the s. griseus proteases a and b. however, there is an additional segment to the pro region ... | 1993 | 7910748 |
| streptomyces griseus protease c. a novel enzyme of the chymotrypsin superfamily. | in this report we describe a novel chymotrypsin-like serine protease produced by streptomyces griseus. the enzyme has been tentatively named s. griseus protease c (sgpc). the gene encoding the enzyme (sprc) was identified and isolated on the basis of its homology to the previously characterized s. griseus protease b (sgpb). the sprc gene encodes a 457-amino acid prepro-mature protein of which only the 255 carboxyl-terminal amino acids are present in the mature enzyme. mature sgpc contains two di ... | 1994 | 8051104 |
| beta-lactamase of lysobacter enzymogenes: cloning, characterization and expression of the gene and comparison of the enzyme to other lactamases. | the gene for the periplasmic beta-lactamase of lysobacter enzymogenes was isolated as part of a 1017 bp ecori fragment and the nucleotide sequence of the gene was determined. it has a g+c content of 71.5% and encodes a 27 amino acid signal sequence and the mature beta-lactamase of 276 amino acids which has a mass of 29,146 da. the enzyme appears to be unique to l. enzymogenes but its amino acid sequence shows a high degree of homology with the amino acid sequences of the lactamase from citrobact ... | 1993 | 8360618 |
| phosphate-starvation induced changes in thiobacillus ferrooxidans. | we have analysed the response of the acidophilic chemolithotroph thiobacillus ferrooxidans to phosphate starvation. cultivation of the bacteria in the absence of added phosphate induced a remarkable filamentation of the cells. polyacrylamide gel electrophoresis revealed several proteins whose levels increased upon phosphate limitation, as well as some polypeptides that were exclusively synthesized under this growth limitation. one of the proteins whose level increased by the lack of phosphate wa ... | 1993 | 8472923 |
| purification and characterization of a novel zinc-proteinase from cultures of aeromonas hydrophila. | while searching for an enzyme capable of breaking epsilon-(gamma-glu)-lys isopeptide bonds cross-linking protein chains, we purified a metallo-proteinase which mimics the action of an isopeptidase on the gamma-chain dimers of cross-linked fibrin. the enzyme is present in the growth medium of the bacterium aeromonas hydrophila, isolated from the intestinal tract of the leech hirudo medicinalis. it is a 19-kda protein which specifically hydrolyzes the gly-ala peptide bond within the gly-gly-ala se ... | 1993 | 8473348 |
| development of techniques for the genetic manipulation of the gliding bacteria lysobacter enzymogenes and lysobacter brunescens. | lysobacter enzymogenes and lysobacter brunescens are gram-negative gliding bacteria that belong to the gamma subgroup of the proteobacteria. as a first step toward a molecular analysis of lysobacter gliding motility, we developed techniques to genetically manipulate these bacteria. cosmid psup106 of the broad host range incompatibility group q (inc q) was introduced into l. enzymogenes and l. brunescens by conjugation and electroporation. psup106 replicated stably in both organisms and conferred ... | 1996 | 8864212 |
| the haemophilus influenzae htra protein is a protective antigen. | the htra gene from two strains of nontypeable haemophilus influenzae has been cloned and sequenced, and the encoded approximately 46-kda htra proteins were found to be highly conserved. h. influenzae htra has approximately 55% identity with the escherichia coli and salmonella typhimurium htra stress response proteins, and expression of the h. influenzae htra gene was inducible by high temperature. recombinant htra (rhtra) was expressed from e. coli, and the purified protein was found to have ser ... | 1998 | 9488373 |
| streptomyces griseus protease b: secretion correlates with the length of the propeptide. | streptomyces griseus protease b, a member of the chymotrypsin superfamily, is encoded by a gene that express a pre-pro-mature protein. during secretion the precursor protein is processed into a mature, fully folded protease. in this study, we constructed a family of genes which encode deletions at the amino-terminal end of the propeptide. the secretion of active protease b was seen to decrease in an exponential manner according to the length of the deletion. the results underscore the intimate r ... | 1998 | 9620979 |
| cloning of a lysobacter enzymogenes gene that encodes an arginyl endopeptidase (endoproteinase arg-c). | screening an expression library of lysobacter enzymogenes dna allowed us to clone a gene encoding a serine protease that cleaves synthetic substrates c-terminal to arg and, to a lesser extent, lys residues. the gene product, which shares sequence homology with the lysyl endopeptidases from l. enzymogenes and achromobacter lyticus, consists of a signal sequence (24 residues), pro-region ( approximately 195 residues), and catalytic domain ( approximately 244 residues). downstream of this gene is a ... | 1998 | 9878833 |
| kinetic stability as a mechanism for protease longevity. | the folding of the extracellular serine protease, alpha-lytic protease (alphalp; ec 3.4.21.12) reveals a novel mechanism for stability that appears to lead to a longer functional lifetime for the protease. for alphalp, stability is based not on thermodynamics, but on kinetics. whereas this has required the coevolution of a pro region to facilitate folding, the result has been the optimization of native-state properties independent of their consequences on thermodynamic stability. structural and ... | 1999 | 10500115 |
| two energetically disparate folding pathways of alpha-lytic protease share a single transition state. | the lysobacter enzymogenes alpha-lytic protease (alphalp) is synthesized with a 166 amino acid pro region (pro) that catalyzes the folding of the 198 amino acid protease into its native conformation. an extraordinary feature of this system is the very high energy barrier (deltag = 30 kcal mol-1) that effectively prevents alphalp from folding in the absence of pro (t1/2 = 1800 years). a pair of mutations has been isolated in the protease that completely suppresses the catalytic defect incurred in ... | 2000 | 10802737 |
| unusual 1h nmr chemical shifts support (his) c(epsilon) 1...o==c h-bond: proposal for reaction-driven ring flip mechanism in serine protease catalysis. | 13c-selective nmr, combined with inhibitor perturbation experiments, shows that the c(epsilon)(1)h proton of the catalytic histidine in resting alpha-lytic protease and subtilisin bpn' resonates, when protonated, at 9.22 ppm and 9.18 ppm, respectively, which is outside the normal range for such protons and approximately 0.6 to 0.8 ppm further downfield than previously reported. they also show that the previous alpha-lytic protease assignments [markley, j. l., neves, d. e., westler, w. m., ibanez ... | 2000 | 10984533 |
| biochemical and genetic characterization of coagulin, a new antilisterial bacteriocin in the pediocin family of bacteriocins, produced by bacillus coagulans i(4). | a plasmid-linked antimicrobial peptide, named coagulin, produced by bacillus coagulans i(4) has recently been reported (b. hyronimus, c. le marrec and m. c. urdaci, j. appl. microbiol. 85:42-50, 1998). in the present study, the complete, unambiguous primary amino acid sequence of the peptide was obtained by a combination of both n-terminal sequencing of purified peptide and the complete sequence deduced from the structural gene harbored by plasmid i(4). data revealed that this peptide of 44 resi ... | 2000 | 11097892 |
| identification of precursor forms of free prostate-specific antigen in serum of prostate cancer patients by immunosorption and mass spectrometry. | the structural features of the free prostate-specific antigen (f-psa) present in human blood have not been clarified up to now, and it is, therefore, not known why f-psa is not complexed by the protease inhibitors that are present in human blood in large amounts. this lack of information is mainly attributable to the low amount of f-psa in serum, which makes the isolation and structural characterization very difficult, especially when only limited amounts of individual sera are available. it has ... | 2001 | 11221890 |
| enzyme specificity under dynamic control ii: principal component analysis of alpha-lytic protease using global and local solvent boundary conditions. | the contributions of conformational dynamics to substrate specificity have been examined by the application of principal component analysis to molecular dynamics trajectories of alpha-lytic protease. the wild-type alpha-lytic protease is highly specific for substrates with small hydrophobic side chains at the specificity pocket, while the met190-->ala binding pocket mutant has a much broader specificity, actively hydrolyzing substrates ranging from ala to phe. based on a combination of multiconf ... | 2001 | 11420442 |
| characterization of an endoprotease (prpl) encoded by a pvds-regulated gene in pseudomonas aeruginosa. | the expression of many virulence factors in pseudomonas aeruginosa is dependent upon environmental conditions, including iron levels, oxygen, temperature, and osmolarity. the virulence of p. aeruginosa pao1 is influenced by the iron- and oxygen-regulated gene encoding the alternative sigma factor pvds, which is regulated through the ferric uptake regulator (fur). we observed that overexpression of pvds in strain pao1 and a deltapvds::gm mutant resulted in increased pyoverdine production and prot ... | 2001 | 11500408 |
| [structure and functions of bacterial proteinase precursors]. | the data on the precursors of bacterial proteases were generalized. the structure and special features of processing of the precursors of bacillary subtilisins, the alpha-lytic protease from lysobacter enzymogenes and the related chymotrypsin-like proteases from streptomyces griseus, and the metalloproteases from bacilli and pseudomonas aeruginosa were discussed. the approaches to producing the precursors and the protease propeptides and to in vitro characterizing them were particularly analyzed ... | 2001 | 11641907 |
| lysobacter strain with high lysyl endopeptidase production. | a new lysyl endopeptidase producing strain, lysobacter sp. ib-9374, was isolated from soil. this strain secreted the endopeptidase to culture medium at 6-12-fold higher levels relative to achromobacter lyticus and lysobacter enzymogenes. the mature lysobacter sp. enzyme was enzymatically identical to achromobacter lysyl endopeptidase bearing lysyl bond specificity, a high peptidase activity, a wide ph optimum, and stability against denaturants. nucleotide sequence analysis of the lysobacter sp. ... | 2002 | 12127482 |
| taxonomic positioning of two biological control agents for plant diseases as lysobacter enzymogenes based on phylogenetic analysis of 16s rdna, fatty acid composition and phenotypic characteristics. | to taxonomically position two bacterial strains conferring biological control activity towards plant diseases. | 2003 | 12752818 |
| molecular characterization and expression in escherichia coli of three beta-1,3-glucanase genes from lysobacter enzymogenes strain n4-7. | lysobacter enzymogenes strain n4-7 produces multiple biochemically distinct extracellular beta-1,3-glucanase activities. the glua, glub, and gluc genes, encoding enzymes with beta-1,3-glucanase activity, were identified by a reverse-genetics approach following internal amino acid sequence determination of beta-1,3-glucanase-active proteins partially purified from culture filtrates of strain n4-7. analysis of glua and gluc gene products indicates that they are members of family 16 glycoside hydro ... | 2003 | 12867444 |
| characterisation of lysobacter enzymogenes (christensen and cook 1978) strain 3.1t8, a powerful antagonist of fungal diseases of cucumber. | isolate 3.1t8 of lysobacter enzymogenes (christensen and cook 1978), originating from the rhizosphere of cucumber and shown to have the potential to control pythium aphanidermatum, is described. the strain produces extracellular proteases and lipases and shows high levels of resistance against streptomycin, kanamycin and tetracycline, but not to chloramphenicol. it shows strong in vitro antibiosis against p. aphanidermatum and several other phytopathogenic fungi. in order to identify the isolate ... | 2003 | 12906383 |
| disabling the folding catalyst is the last critical step in alpha-lytic protease folding. | alpha-lytic protease (alphalp) is an extracellular bacterial pro-protease marked by extraordinary conformational rigidity and a highly cooperative barrier to unfolding. although these properties successfully limit its proteolytic destruction, thereby extending the functional lifetime of the protease, they come at the expense of foldability (t(1/2) = 1800 yr) and thermodynamic stability (native alphalp is less stable than the unfolded species). efficient folding has required the coevolution of a ... | 2004 | 14739318 |
| structural investigations and identification of the extracellular bacteriolytic endopeptidase l1 from lysobacter sp. xl1. | the n-terminal amino acid sequence (23 amino acid residues) and the amino acid composition of the extracellular bacteriolytic enzyme l1 of 21 kd from the bacterium lysobacter sp. xl1 have been determined. the enzyme was hydrolyzed by trypsin, the resulting peptides were isolated, and their primary structures were determined. a high extent of homology (92%) of the n-terminal amino acid sequence and the primary structure of isolated peptides of the enzyme l1 (62 amino acid residues or 31% of prote ... | 2004 | 15193123 |
| a second lysine-specific serine protease from lysobacter sp. strain ib-9374. | a second lysyl endopeptidase gene (lepb) was found immediately upstream of the previously isolated lepa gene encoding a highly active lysyl endopeptidase in lysobacter genomic dna. the lepb gene consists of 2,034 nucleotides coding for a protein of 678 amino acids. amino acid sequence alignment between the lepa and lepb gene products (lepa and lepb) revealed that the lepb precursor protein is composed of a prepeptide (20 amino acids [aa]), a propeptide (184 aa), a mature enzyme (274 aa), and a c ... | 2004 | 15262946 |
| a clp gene homologue belonging to the crp gene family globally regulates lytic enzyme production, antimicrobial activity, and biological control activity expressed by lysobacter enzymogenes strain c3. | lysobacter enzymogenes strain c3, a biological control agent for plant diseases, produces multiple extracellular hydrolytic enzymes and displays antimicrobial activity against various fungal and oomycetous species. however, little is known about the regulation of these enzymes or their roles in antimicrobial activity and biocontrol. a study was undertaken to identify mutants of strain c3 affected in extracellular enzyme production and to evaluate their biocontrol efficacy. a single mini-tn5-lacz ... | 2005 | 15640196 |
| alpha-lytic protease can exist in two separately stable conformations with different his57 mobilities and catalytic activities. | alpha-lytic protease is a bacterial serine protease widely studied as a model system of enzyme catalysis. here we report that lyophilization induces a structural change in the enzyme that is not reversed by redissolution in water. the structural change reduces the mobility of the active-site histidine residue and the catalytic activity of the enzyme. the application of mild pressure to solutions of the altered enzyme reverses the lyophilization-induced structural change and restores the mobility ... | 2005 | 15657134 |
| amino-terminal protein fusions to the trar quorum-sensing transcription factor enhance protein stability and autoinducer-independent activity. | trar of agrobacterium tumefaciens is a member of the luxr family of quorum-sensing transcription factors and regulates genes required for conjugation and vegetative replication of the tumor-inducing (ti) plasmid in the presence of the autoinducer 3-oxooctanoyl-homoserine lactone (oohl). in the absence of oohl, trar is rapidly destroyed by proteolysis, suggesting that this ligand is required for trar folding. to date, no trar variant has been found that is active in the absence of oohl. in this s ... | 2005 | 15687185 |
| hydrolase and glycosynthase activity of endo-1,3-beta-glucanase from the thermophile pyrococcus furiosus. | pyrococcus furiosus laminarinase (lama, pf0076) is an endo-glycosidase that hydrolyzes beta-1,3-glucooligosaccharides, but not beta-1,4-gluco-oligosaccharides. we studied the specificity of lama towards small saccharides by using 4-methylumbelliferyl beta-glucosides with different linkages. besides endo-activity, wild-type lama has some exo-activity, and catalyzes the hydrolysis of mixed-linked oligosaccharides (glcbeta4glcbeta3glcbeta-mu (glc = glucosyl, mu = 4-methylumbelliferyl)) with both be ... | 2004 | 15810439 |
| functional analysis of the burkholderia cenocepacia zmpa metalloprotease. | burkholderia cenocepacia zmpa is expressed as a preproenzyme typical of thermolysin-like proteases such as pseudomonas aeruginosa lasb and bacillus thermoproteolyticus thermolysin. the zmpa gene was expressed using the ppro-exhta his(6) tag expression system, which incorporates a six-his tag at the n-terminal end of the protein, and recombinant zmpa was purified using ni-nitrilotriacetic acid affinity chromatography. upon refolding of the recombinant his(6)-pre-pro-zmpa (62 kda), the fusion prot ... | 2005 | 15968051 |
| suppression of damping-off disease in host plants by the rhizoplane bacterium lysobacter sp. strain sb-k88 is linked to plant colonization and antibiosis against soilborne peronosporomycetes. | we previously demonstrated that xanthobaccin a from the rhizoplane bacterium lysobacter sp. strain sb-k88 suppresses damping-off disease caused by pythium sp. in sugar beet. in this study we focused on modes of lysobacter sp. strain sb-k88 root colonization and antibiosis of the bacterium against aphanomyces cochlioides, a pathogen of damping-off disease. scanning electron microscopic analysis of 2-week-old sugar beet seedlings from seeds previously inoculated with sb-k88 revealed dense coloniza ... | 2005 | 16000790 |
| the role of clp-regulated factors in antagonism against magnaporthe poae and biological control of summer patch disease of kentucky bluegrass by lysobacter enzymogenes c3. | a global regulator was previously identified in lysobacter enzymogenes c3, which when mutated, resulted in strains that were greatly reduced in the expression of traits associated with fungal antagonism and devoid of biocontrol activity towards bipolaris leaf-spot of tall fescue and pythium damping-off of sugarbeet. a clp gene homologue belonging to the crp gene family was found to globally regulate enzyme production, antimicrobial activity, and biological control activity expressed by lysobacte ... | 2005 | 16234871 |
| distinct ceramide synthases regulate polarized growth in the filamentous fungus aspergillus nidulans. | in filamentous fungi, the stabilization of a polarity axis is likely to be a pivotal event underlying the emergence of a germ tube from a germinating spore. recent results implicate the polarisome in this process and also suggest that it requires localized membrane organization. here, we employ a chemical genetic approach to demonstrate that ceramide synthesis is necessary for the formation of a stable polarity axis in the model fungus aspergillus nidulans. we demonstrate that a novel compound ( ... | 2006 | 16394102 |
| lysobacter koreensis sp. nov., isolated from a ginseng field. | strain dae16t, a gram-negative, non-spore-forming, rod-shaped bacterium, was isolated from the soil of a ginseng field in south korea and characterized in order to determine its taxonomic position. 16s rrna gene sequence analysis revealed that strain dae16t belongs to the gammaproteobacteria and had the highest degree of sequence similarity to lysobacter gummosus atcc 29489t (97.1 %), lysobacter antibioticus dsm 2044t (96.6 %), lysobacter enzymogenes dsm 2043t (96.2 %), lysobacter concretionis k ... | 2006 | 16403891 |
| mapping of an internal protease cleavage site in the ssy5p component of the amino acid sensor of saccharomyces cerevisiae and functional characterization of the resulting pro- and protease domains by gain-of-function genetics. | ssy5p is a 77-kda protein believed to be a component of the sps amino acid sensor complex in the plasma membrane of saccharomyces cerevisiae. ssy5p has been suggested to be a chymotrypsin-like serine protease that activates the transcription factor stp1p upon exposure of the yeast to extracellular amino acid. here we overexpressed and partially purified ssy5p to improve our understanding of its structure and function. antibodies against ssy5p expressed in escherichia coli were isolated and used ... | 2006 | 16524914 |
| revisiting the cellulosimicrobium cellulans yeast-lytic beta-1,3-glucanases toolbox: a review. | cellulosimicrobium cellulans (also known with the synonyms cellulomonas cellulans, oerskovia xanthineolytica, and arthrobacter luteus) is an actinomycete that excretes yeast cell wall lytic enzyme complexes containing endo-beta-1,3-glucanases [ec 3.2.1.39 and 3.2.1.6] as key constituents. three genes encoding endo-beta-1,3-glucanases from two c. cellulans strains have been cloned and characterised over the past years. the betaglii and betagliia genes from strain dsm 10297 (also known as o. xanth ... | 2006 | 16545129 |
| two novel species, lysobacter daejeonensis sp. nov. and lysobacter yangpyeongensis sp. nov., isolated from korean greenhouse soils. | two bacterial strains were isolated from greenhouse soils of daejeon and yangpyeong regions in korea. the strains, designated gh1-9t and gh19-3t, were gram-negative and aerobic, with rod-shaped cells. their dna g+c contents were 61.7 and 67.3 mol%, respectively. the major fatty acids of strain gh1-9t were iso-c16 : 0, iso-c15 : 0, iso-c14 : 0, iso-c17 : 1omega9c and iso-c11 : 0 3-oh and the major components of strain gh19-3t were iso-c16 : 0, iso-c15 : 0, c16 : 1omega7c alcohol, iso-c17 : 1omega ... | 2006 | 16627636 |
| structure and biosynthesis of heat-stable antifungal factor (hsaf), a broad-spectrum antimycotic with a novel mode of action. | a screen for antifungal compounds from lysobacter enzymogenes strain c3, a bacterial biological control agent of fungal diseases, has previously led to the isolation of heat-stable antifungal factor (hsaf). hsaf exhibits inhibitory activities against a wide range of fungal species and shows a novel mode of antifungal action by disrupting the biosynthesis of a distinct group of sphingolipids. we have now determined the chemical structure of hsaf, which is identical to that of dihydromaltophilin, ... | 2007 | 17074795 |
| lysobacter enzymogenes subsp. enzymogenes christensen and cook 1978, l. enzymogenes subsp. cookii christensen 1978 and streptococcus casseliflavus (mundt and graham 1968) vaughan et al. 1978 should have been cited in the approved lists of bacterial names. request for an opinion. | lysobacter enzymogenes subsp. enzymogenes christensen and cook 1978, l. enzymogenes subsp. cookii christensen 1978 and streptococcus casseliflavus (mundt and graham 1968) vaughan et al. 1978 were inadvertently omitted from the approved lists of bacterial names. according to rule 24a, note 1, the authors request that these names be considered as included in these lists. | 2006 | 17082416 |
| lysobacter niabensis sp. nov. and lysobacter niastensis sp. nov., isolated from greenhouse soils in korea. | two bacterial strains, designated gh34-4(t) and gh41-7(t), were isolated from greenhouse soil cultivated with cucumber. the bacteria were strictly aerobic, gram-negative, rod-shaped and oxidase- and catalase-positive. 16s rrna gene sequence analysis indicated that these strains belong to the genus lysobacter within the gammaproteobacteria. strain gh34-4(t) showed highest sequence similarity to lysobacter yangpyeongensis gh19-3(t) (97.5 %) and lysobacter koreensis dae16(t) (96.4 %), and strain gh ... | 2007 | 17329782 |
| identification of critical residues in the propeptide of lasa protease of pseudomonas aeruginosa involved in the formation of a stable mature protease. | lasa protease is a 20-kda elastolytic and staphylolytic enzyme secreted by pseudomonas aeruginosa. lasa is synthesized as a preproenzyme that undergoes proteolysis to remove a 22-kda amino-terminal propeptide. like the propeptides of other bacterial proteases, the lasa propeptide may act as an intramolecular chaperone that correctly folds the mature domain into an active protease. to locate regions of functional importance within prolasa, linker-scanning insertional mutagenesis was employed usin ... | 2007 | 17351039 |
| quantification of cysteine oxidation in human estrogen receptor by mass spectrometry. | redox-dependent modifications of sulfhydryl groups within the two cys4 zinc fingers of the estrogen receptor dna-binding domain (er-dbd) result in structural damage and loss of er dna-binding function, which parallels the situation observed in many er-positive breast cancers. quantitation of the redox status of cysteinyl thiols within er-dbd employed cysteine-specific oxidants to induce varying degrees of oxidation in recombinant er, followed by differential alkylation with the stable isotopic l ... | 2007 | 17373775 |
| identification of bacteria on the surface of clinically infected and non-infected prosthetic hip joints removed during revision arthroplasties by 16s rrna gene sequencing and by microbiological culture. | it has been postulated that bacteria attached to the surface of prosthetic hip joints can cause localised inflammation, resulting in failure of the replacement joint. however, diagnosis of infection is difficult with traditional microbiological culture methods, and evidence exists that highly fastidious or non-cultivable organisms have a role in implant infections. the purpose of this study was to use culture and culture-independent methods to detect the bacteria present on the surface of prosth ... | 2007 | 17501992 |
| molecular identification of bacteria in bronchoalveolar lavage fluid from children with cystic fibrosis. | culture of bronchoalveolar lavage fluid (balf) is the gold standard for detection of pathogens in the lower airways in cystic fibrosis (cf). however, current culture results do not explain all clinical observations in cf, including negative culture results during pulmonary exacerbation and inflammation in the absence of pathogens. we hypothesize that organisms not routinely identified by culture occur in the cf airway and may contribute to disease. to test this hypothesis we used a culture-indep ... | 2007 | 18077362 |
| adaptable molecular interactions guide phosphorylation of the sr protein asf/sf2 by srpk1. | the sr (arginine-serine rich) protein asf/sf2 (also called human alternative splicing factor), an essential splicing factor, contains two functional modules consisting of tandem rna recognition motifs (rrms; rrm1-rrm2) and a c-terminal arginine-serine repeat region (rs domain, a domain rich in arginine-serine repeats). the sr-specific protein kinase (srpk) 1 phosphorylates the rs domain at multiple serines using a directional (c-terminal-to-n-terminal) and processive mechanism--a process that di ... | 2008 | 18687337 |
| flavobacterium sp. strain 4221 and pedobacter sp. strain 4236 beta-1,3-glucanases that are active at low temperatures. | secretion of beta-1,3-glucanases by the arctic bacterial isolates 4221 and 4236, related to the genera flavobacterium and pedobacter, was discovered. escherichia coli and lactococcus lactis expression of beta-1,3-glucanases glc4221-1 and glc4236-1 from the respective isolates was achieved. the enzymes hydrolyzed fungal cell walls and retained activity at low temperatures. | 2008 | 18806001 |
| mutagenesis of beta-1,3-glucanase genes in lysobacter enzymogenes strain c3 results in reduced biological control activity toward bipolaris leaf spot of tall fescue and pythium damping-off of sugar beet. | abstract lysobacter enzymogenes produces extracellular lytic enzymes capable of degrading the cell walls of fungi and oomycetes. many of these enzymes, including beta-1,3-glucanases, are thought to contribute to the biological control activity expressed by several strains of the species. l. enzymogenes strain c3 produces multiple extracellular beta-1,3-glucanases encoded by the glua, glub, and gluc genes. analysis of the genes indicates they are homologous to previously characterized genes in th ... | 2005 | 18943787 |
| induced resistance as a mechanism of biological control by lysobacter enzymogenes strain c3. | abstract induced resistance was found to be a mechanism for biological control of leaf spot, caused by bipolaris sorokiniana, in tall fescue (festuca arundinacea) using the bacterium lysobacter enzymogenes strain c3. resistance elicited by c3 suppressed germination of b. sorokiniana conidia on the phylloplane in addition to reducing the severity of leaf spot. the pathogen-inhibitory effect could be separated from antibiosis by using heat-inactivated cells of c3 that retained no antifungal activi ... | 2003 | 18944093 |
| an antibiotic complex from lysobacter enzymogenes strain c3: antimicrobial activity and role in plant disease control. | lysobacter enzymogenes c3 is a bacterial biological control agent that exhibits antagonism against multiple fungal pathogens. its antifungal activity was attributed in part to lytic enzymes. in this study, a heat-stable antifungal factor (hsaf), an antibiotic complex consisting of dihydromaltophilin and structurally related macrocyclic lactams, was found to be responsible for antagonism by c3 against fungi and oomycetes in culture. hsaf in purified form exhibited inhibitory activity against a wi ... | 2008 | 18944294 |
| preparation and characterization of salmon calcitonin-biotin conjugates. | this study was performed to prepare and characterize the biotinylated salmon calcitonin (sct) for oral delivery and evaluate the hypocalcemic effect of biotinylated-scts in rats. biotinylated scts was characterized by using high performance liquid chromatography (hplc) and malditof-ms. the effect of biotinylation on permeability across caco-2 cell monolayers was examined. their hypocalcemic effect was determined in rats. mono- and di-bio-scts were separated by reverse phase hplc. the molecular w ... | 2008 | 19082740 |
| influence of lysobacter enzymogenes strain c3 on nematodes. | chitinolytic microflora may contribute to biological control of plant-parasitic nematodes by causing decreased egg viability through degradation of egg shells. here, the influence of lysobacter enzymogenes strain c3 on caenorhabditis elegans, heterodera schachtii, meloidogyne javanica, pratylenchus penetrans, and aphelenchoides fragariae is described. exposure of c. elegans to l. enzymogenes strain c3 on agar resulted in almost complete elimination of egg production and death of 94% of hatched j ... | 2006 | 19259452 |
| lysobacter oryzae sp. nov., isolated from the rhizosphere of rice (oryza sativa l.). | the taxonomic position of a novel bacterial strain, yc6269(t), isolated from the rhizosphere of rice (oryza sativa l.) managed under no-tillage practice in jinju, south korea, was studied using polyphasic approach. cells of the strain were gram-negative, rod-shaped and facultatively anaerobic. the novel strain grew at a temperature of 15-42 degrees c (optimum at 28 degrees c). growth of the strain occurred between ph 5.5 and 11.0, with an optimum at ph 7.0-8.0. the g+c content of the total dna w ... | 2009 | 19329586 |
| regiospecific phosphorylation control of the sr protein asf/sf2 by srpk1. | sr proteins (splicing factors containing arginine-serine repeats) are essential factors that control the splicing of precursor mrna by regulating multiple steps in spliceosome development. the prototypical sr protein asf/sf2 (human alternative splicing factor) contains two n-terminal rna recognition motifs (rrms) (rrm1 and rrm2) and a 50-residue c-terminal rs (arginine-serine-rich) domain that can be phosphorylated at numerous serines by the protein kinase sr-specific protein kinase (srpk) 1. th ... | 2009 | 19477182 |
| 'lysobacter enzymogenes ssp. cookii ' christensen 1978 should be recognized as an independent species, lysobacter cookii sp. nov. | 'lysobacter enzymogenes ssp. cookii' was proposed by christensen and cook in 1978; however, this subspecies name has not been cited in the approved lists of bacterial names and therefore the nomenclature has not been validated. in our genetic approach to clarify the relationships of the designated type strain of 'l. enzymogenes ssp. cookii' pagu 1119 (genbank accession number atcc29488) within the genus lysobacter revealed that the strain was closely related to lysobacter capsiciyc5194(t) (99.4% ... | 2009 | 19659731 |
| lysobacter soli sp. nov., isolated from soil of a ginseng field. | strain dcy21(t), a gram-negative, gliding and rod-shaped aerobic bacterium was isolated from soil of a ginseng field in the republic of korea and characterized using a polyphasic approach in order to determine its taxonomic position. comparative 16s rrna gene sequence analysis revealed that strain dcy21(t) clustered with the species of the genus lysobacter. it was closely related to lysobacter gummosus lmg 8763(t) (97.9 %), lysobacter capsici yc5194(t) (97.6 %), lysobacter antibioticus dsm 2044( ... | 2010 | 19684312 |
| stenotrophomonas and lysobacter: ubiquitous plant-associated gamma-proteobacteria of developing significance in applied microbiology. | the exploration of new source materials and the use of alternative isolation and identification methods have led to rapid expansion in the knowledge of diversity; in lysobacter, 11 new species having been described since 2005, and in stenotrophomonas with six new species since 2000. the new species of lysobacter, isolated by dilution and direct plating on standard media, differ in several key phenotypic properties from those obtained by enrichment on complex polysaccharides in the original descr ... | 2010 | 19702860 |
| specific detection of lysobacter enzymogenes (christensen and cook 1978) strain 3.1t8 with taqman pcr. | to develop a strain-specific taqman pcr method for detecting and quantifying the biocontrol strain lysobacter enzymogenes 3.1t8. | 2010 | 19732213 |
| phylogenetic and multivariate analyses to determine the effects of different tillage and residue management practices on soil bacterial communities. | bacterial communities are important not only in the cycling of organic compounds but also in maintaining ecosystems. specific bacterial groups can be affected as a result of changes in environmental conditions caused by human activities, such as agricultural practices. the aim of this study was to analyze the effects of different forms of tillage and residue management on soil bacterial communities by using phylogenetic and multivariate analyses. treatments involving zero tillage (zt) and conven ... | 2010 | 20382808 |
| common biosynthetic origins for polycyclic tetramate macrolactams from phylogenetically diverse bacteria. | a combination of small molecule chemistry, biosynthetic analysis, and genome mining has revealed the unexpected conservation of polycyclic tetramate macrolactam biosynthetic loci in diverse bacteria. initially our chemical analysis of a streptomyces strain associated with the southern pine beetle led to the discovery of frontalamides a and b, two previously undescribed members of this antibiotic family. genome analyses and genetic manipulation of the producing organism led to the identification ... | 2010 | 20547882 |
| mechanism of dephosphorylation of the sr protein asf/sf2 by protein phosphatase 1. | sr proteins are essential splicing factors whose function is controlled by multi-site phosphorylation of a c-terminal domain rich in arginine-serine repeats (rs domain). the protein kinase srpk1 has been shown to polyphosphorylate the n-terminal portion of the rs domain (rs1) of the sr protein asf/sf2, a modification that promotes nuclear entry of this splicing factor and engagement in splicing function. later, dephosphorylation is required for maturation of the spliceosome and other rna process ... | 2010 | 20826166 |
| targeted discovery of polycyclic tetramate macrolactams from an environmental streptomyces strain. | a targeted polymerase chain reaction (pcr)-based screening approach was used to identify candidate polycyclic tetramate macrolactam (ptm) biosynthetic gene clusters in environmental streptomyces isolates. isolation and characterization of the small molecules produced by one of the strains confirmed the production of two new ptms (clifednamides a, 4, and b, 5) and, more generally, the utility of using a targeted approach for the discovery of new members of this interesting class. | 2010 | 20843016 |
| lysobacter korlensis sp. nov. and lysobacter bugurensis sp. nov., isolated from soil in north-west china. | two gram-negative, rod-shaped, gliding and yellow-pigmented bacterial strains, designated zld-17(t) and zld-29(t), were isolated from arid soil samples collected from xinjiang province, north-west china, and subjected to a polyphasic taxonomic study. both novel strains requires 1-2% (w/v) sea salts for optimal growth. phylogenetic analysis based on 16s rrna gene sequences indicated that these two strains belong to the genus lysobacter within the gammaproteobacteria. strain zld-17(t) showed the h ... | 2010 | 20952549 |
| biosynthesis of hsaf, a tetramic acid-containing macrolactam from lysobacter enzymogenes. | hsaf was isolated from lysobacter enzymogenes , a bacterium used in the biological control of fungal diseases of plants. structurally, it is a tetramic acid-containing macrolactam fused to a tricyclic system. hsaf exhibits a novel mode of action by disrupting sphingolipids important to the polarized growth of filamentous fungi. here we describe the hsaf biosynthetic gene cluster, which contains only a single-module polyketide synthase/nonribosomal peptide synthetase (pks/nrps), although the bios ... | 2010 | 21171605 |
| stimulants of toll-like receptors 2 and 4 are elevated in saliva of periodontitis patients compared with healthy subjects. | because the absorption of stimulants of toll-like receptor (tlr)2 and tlr4 from the gastrointestinal tract into the circulation has been proposed to promote the development of atherosclerosis and insulin resistance, we aimed to quantify the abundance of stimulants of tlr2 and tlr4 in human saliva. | 2011 | 21284689 |
| indigenous populations of three closely related lysobacter spp. in agricultural soils using real-time pcr. | previous research had shown that three closely related species of lysobacter, i.e., lysobacter antibioticus, lysobacter capsici, and lysobacter gummosus, were present in different rhizoctonia-suppressive soils. however, the population dynamics of these three lysobacter spp. in different habitats remains unknown. therefore, a specific primer-probe combination was designed for the combined quantification of these three lysobacter spp. using taqman. strains of the three target species were efficien ... | 2011 | 21448673 |
| induction of cell wall thickening by the antifungal compound dihydromaltophilin disrupts fungal growth and is mediated by sphingolipid biosynthesis. | dihydromaltophilin (heat-stable antifungal factor [hsaf]) is an antifungal metabolite produced in lysobacter enzymogenes biocontrol strain c3. this compound induces cell wall thickening in aspergillus nidulans. here we show that the cell wall thickening is a general response to hsaf in diverse fungal species. in the a. nidulans model, the thickened cell wall negatively affects hyphal growth. growth of hsaf-pre-treated hyphae failed to resume at hyphal tips with thick cell wall and the actin cabl ... | 2009 | 21462551 |
| control of glucosylceramide production and morphogenesis by the bar1 ceramide synthase in fusarium graminearum. | the contribution of plasma membrane proteins to the virulence of plant pathogenic fungi is poorly understood. accordingly, the objective of this study was to characterize the acyl-coa dependent ceramide synthase bar1 (previously implicated in plasma membrane organization) in the wheat pathogen fusarium graminearum. the role of bar1 in mediating cell membrane organization was confirmed as δbar1 mutants failed to display a distinct sterol-rich domain at the hyphal tip. the δbar1 mutants were non-p ... | 2011 | 21559419 |
| regulating sr protein phosphorylation through regions outside the kinase domain of srpk1. | sr proteins (splicing factors containing arginine-serine repeats) are essential splicing factors whose phosphorylation by the sr-specific protein kinase (srpk) family regulates nuclear localization and mrna processing activity. in addition to an n-terminal extension with unknown function, srpks contain a large, nonhomologous spacer insert domain (sid) that bifurcates the kinase domain and anchors the kinase in the cytoplasm through interactions with chaperones. while structures for the kinase do ... | 2011 | 21600902 |
| genetic diversity and phylogeny of antagonistic bacteria against phytophthora nicotianae isolated from tobacco rhizosphere. | the genetic diversity of antagonistic bacteria from the tobacco rhizosphere was examined by boxair-pcr, 16s-rflp, 16s rrna sequence homology and phylogenetic analysis methods. these studies revealed that 4.01% of the 6652 tested had some inhibitory activity against phytophthora nicotianae. boxair-pcr analysis revealed 35 distinct amplimers aligning at a 91% similarity level, reflecting a high degree of genotypic diversity among the antagonistic bacteria. a total of 25 16s-rflp patterns were iden ... | 2011 | 21686169 |
| Identification and characterization of the anti-methicillin-resistant Staphylococcus aureus WAP-8294A2 biosynthetic gene cluster from Lysobacter enzymogenes OH11. | Lysobactor enzymogenes strain OH11 is an emerging biological control agent of fungal and bacterial diseases. We recently completed its genome sequence and found it contains a large number of gene clusters putatively responsible for the biosynthesis of nonribosomal peptides and polyketides, including the previously identified antifungal dihydromaltophilin (HSAF). One of the gene clusters contains two huge open reading frames, together encoding 12 modules of nonribosomal peptide synthetases (NRPS) ... | 2011 | 21930890 |
| fungal glucosylceramides: from structural components to biologically active targets of new antimicrobials. | the first work reporting synthesis of glucosylceramide (cerebrin, glccer) by yeasts was published in 1930. during approximately 70 years members of this class of glycosphingolipids (gsl) were considered merely structural components of plasma membrane in fungi. however, in the last decade glccer was reported to be involved with fungal growth, differentiation, virulence, immunogenicity, and lipid raft architecture in at least two human pathogens. fungal glccer are structurally distinct from their ... | 2011 | 22025918 |
| Proteinase K-resistant material in ARR/VRQ sheep brain affected with classical scrapie is composed mainly of VRQ prion protein. | Classical scrapie is a prion disease in sheep and goats. In sheep, susceptibility to disease is genetically influenced by single amino acid substitutions. Genetic breeding programs aimed at enrichment of arginine-171 (171R) prion protein (PrP), the so-called ARR allele, in the sheep population have been demonstrated to be effective in reducing the occurrence of classical scrapie in the field. Understanding the molecular basis for this reduced prevalence would serve the assessment of ARR adaptati ... | 2011 | 21917981 |