| flagellar hook and basal complex of caulobacter crescentus. | intact bacterial flagella possessing a membrane-free hook and basal complex were purified from caulobacter crescentus cb15, as well as from mutants which synthesize incomplete flagella. the basal body consisted of five rings mounted on a rod. two rings were in the hook-proximal upper set, and three rings (two narrow and one wide) were in the lower set. the diameters of the two upper rings differed, being 32 and 21 nm, respectively. the lower rings were all approximately 21 nm in diameter, althou ... | 1979 | 457596 |
| expression of the mosquitocidal toxins of bacillus sphaericus and bacillus thuringiensis subsp. israelensis by recombinant caulobacter crescentus, a vehicle for biological control of aquatic insect larvae. | in the quest for effective control of mosquitoes, attention has turned increasingly to strains of the bacteria bacillus sphaericus and bacillus thuringiensis subsp. israelensis, which produce potent toxins with specific mosquitocidal activities. however, sedimentation of the bacterial spores limits the duration of effective control after field application of these bacilli. we describe here the cloning of genes encoding the 51.4- and 41.9-kda toxins from b. sphaericus 2297, the 100-kda toxin from ... | 1992 | 1575492 |
| transcriptional analysis of the major surface array gene of caulobacter crescentus. | the major component of the paracrystalline surface array of caulobacter crescentus cb15 and one of the most abundant cellular proteins is a protein designated 130k. we have determined the dna sequence of the 5' portion of the 130k gene, including the n-terminal one-third of the protein coding region, and analyzed the transcription of the gene. the site of transcription initiation was determined by s1 mapping of caulobacter rna. although the dna sequence upstream from the transcription start site ... | 1988 | 3049545 |
| three-dimensional reconstruction of the flagellar filament of caulobacter crescentus. a flagellin lacking the outer domain and its amino acid sequence lacking an internal segment. | we obtained a three-dimensional reconstruction of the flagellar filament of caulobacter crescentus cb15 from electron micrographs of negatively stained preparations. the c. crescentus filament appears, both in negative stain and in the frozen-hydrated state, significantly smoother and narrower than other filaments. its helical symmetry, and unit cell size, however, are similar to that of other filaments. although the molecular weight of the c. crescentus flagellin is about half that of other pla ... | 1988 | 3172239 |
| regulation of polar morphogenesis in caulobacter crescentus. | deoxyribonucleic acid (dna) phage phi cbk-resistant nonmotile mutants of caulobacter crescentus cb15 were examined for their formation of polar surface structures (a stalk, a single flagellum, pili, and dna phage receptors). these mutants were devoid of pili and dna phage receptors and simultaneously defective either in both stalk formation and flagellar activity (stalk-defective type) or in the formation of normal flagella (flagella-defective type). dna phage phi cr30-mediated transductions rev ... | 1981 | 6109706 |
| periodic surface array in caulobacter crescentus: fine structure and chemical analysis. | a periodic array structure on the cell surface of caulobacter crescentus cb15 was revealed by electron microscopy of the cell envelope, using negative staining, thin-sectioning, and freeze-etching. this structural layer has been isolated from liquid cultures, in which large pieces of the two-dimensional array are shed by cells grown to high density. often areas of intact array corresponding to the entire cell surface could be found. the hexagonally arranged structure was highly ordered and had a ... | 1981 | 6165711 |
| cloning of the major protein of the caulobacter crescentus periodic surface layer: detection and characterization of the cloned peptide by protein expression assays. | a precisely ordered crystalline array is found on the surface of the bacterium caulobacter crescentus cb15. using an immunological assay, we identified recombinant bacteriophage clones expressing the predominant protein of this structure from a lambda 1059 library of c. crescentus cb15 dna. a single 4.4-kilobase hindiii fragment encoded a polypeptide whose antigenic determinants, molecular weight, and peculiar solubilization properties were identical with those of the authentic predominant polyp ... | 1984 | 6209263 |
| the nucleotide sequence of the mr = 28,500 flagellin gene of caulobacter crescentus. | the dna sequences which encode the mr = 28,500 flagellin polypeptide of caulobacter crescentus cb15 have been determined. the size of the protein, deduced from its dna sequence (276 amino acids), is in agreement with its apparent molecular weight as measured by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. the distribution of arginine residues within the protein sequence encoded by the gene correlates with their relative location as predicted by peptide alignment analysis (gill, p.r ... | 1983 | 6305939 |
| copper-zinc superoxide dismutase from caulobacter crescentus cb15. a novel bacteriocuprein form of the enzyme. | a bacteriocuprein is a copper- and zinc-containing superoxide dismutase isolated from a bacterium. until recently, the first and only documented bacteriocuprein was that from the marine bacterium photobacterium leiognathi, which lives symbiotically with leiognathid fishes. a new bacteriocuprein has been discovered, purified, and characterized from the free living, non-symbiotic bacterium, caulobacter crescentus cb15. in its native molecular weight, homodimeric subunit structure, specific activit ... | 1982 | 7050107 |
| genetic organization and transposition properties of is511. | is511 is an endogenous insertion sequence (is) of the bacterium caulobacter crescentus strain cb15 and it is the first caulobacter is to be characterized at the molecular level. we determined the 1266-bp nucleotide sequence of is511 and investigated its genetic organization, relationship to other iss, and transposition properties. is511 belongs to a distinct branch of the is3 family that includes isr1, is476, and is1222, based on nucleotide sequence similarity. the nucleotide sequence of is511 e ... | 1997 | 9180700 |
| cau-1, a subclass b3 metallo-beta-lactamase of low substrate affinity encoded by an ortholog present in the caulobacter crescentus chromosome. | the sequenced chromosome of caulobacter crescentus cb15 encodes a hypothetical protein that exhibits significant similarity (30 to 35% identical residues) to metallo-beta-lactamases of subclass b3. an allelic variant of this gene (divergent by 3% of its nucleotides) was cloned in escherichia coli from c. crescentus type strain dsm4727. expression studies confirmed the metallo-beta-lactamase activity of its product, cau-1. the enzyme produced in e. coli was purified by two ion-exchange chromatogr ... | 2002 | 12019096 |
| biochemical and molecular characterization of poly(aspartic acid) hydrolase-2 from sphingomonas sp. kt-1. | poly(aspartic acid) (paa) hydrolase-2 was purified from crude soluble cellular extracts of sphingomonas sp. kt-1 (jcm10459) and characterized to elucidate the mechanism of alpha,beta-poly(d,l-aspartic acid) (tpaa) biodegradation. the molecular mass of paa hydrolase-2 was 42 kda, and the isoelectric point was 9.6. the optimum values of ph and temperature for the hydrolysis of alpha-di(l-aspartic acid) by paa hydrolase-2 were 7.0 and 55 degrees c, respectively. the effect of inhibitors on the hydr ... | 2003 | 12959596 |
| cloning and functional analysis of the sequences flanking mini-tn5 in the magnetosomes deleted mutant nm4 of magnetospirillum gryphiswaldense msr-1. | a magnetosome deleted mutant nm4 of magnetospirillum gryphiswaldense msr-1 was generated by mini-tn5 transposon mutagenesis, and a 5045-bp fragment flanking mini-tn5 in nm4 was cloned by anchored pcr. sequencing analysis showed that this fragment involved six putative open reading frames (orfs); the mini-tn5 was inserted into orf4. functional complementary test indicated that the 5045-bp fragment was required for biosynthesis of magnetosomes in m. gryphiswaldense msr-1. the protein encoded by or ... | 2005 | 16483136 |
| structure of a novel lipid a obtained from the lipopolysaccharide of caulobacter crescentus. | caulobacter crescentus cb15 is a dimorphic bacterium that is best known as a prokaryotic model for cell development. however, it is also being exploited in biotechnology, where the crystalline surface (s-layer) protein secretion system has been adapted for heterologous protein display or secretion. because the s-layer attaches to the cell surface via lipopolysaccharide (lps) and since the lps represents a potential endotoxin contaminant of recombinant proteins, the lipid a component was examined ... | 2008 | 18387917 |
| functional identification of incorrectly annotated prolidases from the amidohydrolase superfamily of enzymes. | the substrate profiles for two proteins from caulobacter crescentus cb15 (cc2672 and cc3125) and one protein (sgx9359b) derived from a dna sequence ( gi|44368820 ) isolated from the sargasso sea were determined using combinatorial libraries of dipeptides and n-acyl derivatives of amino acids. these proteins are members of the amidohydrolase superfamily and are currently misannotated in ncbi as catalyzing the hydrolysis of l-xaa-l-pro dipeptides. cc2672 was shown to catalyze the hydrolysis of l-x ... | 2009 | 19281183 |
| comparative analysis of caulobacter chromosome replication origins. | caulobacter crescentus (cb15) initiates chromosome replication only in stalked cells and not in swarmers. to better understand this dimorphic control of chromosome replication, we isolated replication origins (oris) from freshwater caulobacter (fwc) and marine caulobacter (mcs) species. previous studies implicated integration host factor (ihf) and ccrm dna methylation sites in replication control. however, ori ihf and ccrm sites identified in the model fwc cb15 were only conserved among closely ... | 2009 | 19332823 |
| two site-directed mutations are required for the conversion of a sugar dehydratase into an aminotransferase. | l-colitose and d-perosamine are unusual sugars found in the o-antigens of some gram-negative bacteria such as escherichia coli, vibrio cholerae, and salmonella enterica, among others. the biosynthetic pathways for these two sugars begin with the formation of gdp-mannose from d-mannose 1-phosphate and gtp followed by the subsequent dehydration and oxidation of gdp-mannose to yield gdp-4-keto-6-deoxymannose. following the production of gdp-4-keto-6-deoxymannose, the two pathways diverge. in the ca ... | 2009 | 19402712 |
| mutants of caulobacter crescentus resistant to beta-lactam antibiotics. | a number of mutants of caulobacter crescentus cb15 resistant ot ampicillin were isolated. the mutants differred in their resistance to several beta-lactam antibiotics. no differences in composition of the penicillin-binding proteins of the mutants compared to the parental strain, or in the affinity of these proteins to penicillin or ampicillin were found. the mutants were found to differ from the parent and also in many cases from each other in outer membrane protein composition. | 1986 | 21542390 |
| identification, crystallization and preliminary x-ray diffraction analysis of esterase a from caulobacter crescentus cb15, a family viii lipolytic enzyme. | the structures and functions of family viii lipolytic enzymes, which have moderate sequence identity to class c β-lactamases and penicillin-binding proteins, are largely unknown. here, the x-ray crystallographic study of a family viii esterase from caulobacter crescentus cb15 (ccesta) is described. sequence analysis revealed that ccesta has a conserved serine residue within the s-x-x-k motif which acts as a catalytic nucleophile. recombinant protein containing an n-terminal his tag was expressed ... | 2012 | 22691788 |
| biochemical and structural analysis of a novel esterase from caulobacter crescentus related to penicillin-binding protein (pbp). | considering that the prevalence of antibiotic-resistant pathogenic bacteria is largely increasing, a thorough understanding of penicillin-binding proteins (pbps) is of great importance and crucial significance because this enzyme family is a main target of β-lactam-based antibiotics. in this work, combining biochemical and structural analysis, we present new findings that provide novel insights into pbps. here, a novel pbp homologue (ccesta) from caulobacter crescentus cb15 was characterized usi ... | 2016 | 27905486 |
| a novel aldose-aldose oxidoreductase for co-production of d-xylonate and xylitol from d-xylose with saccharomyces cerevisiae. | an open reading frame cc1225 from the caulobacter crescentus cb15 genome sequence belongs to the gfo/idh/moca protein family and has 47 % amino acid sequence identity with the glucose-fructose oxidoreductase from zymomonas mobilis (zm gfor). we expressed the orf cc1225 in the yeast saccharomyces cerevisiae and used a yeast strain expressing the gene coding for zm gfor as a reference. cell extracts of strains overexpressing cc1225 (renamed as cc aaor) showed some zm gfor type of activity, produci ... | 2015 | 26264136 |
| toxin inhibition in c. crescentus vapbc1 is mediated by a flexible pseudo-palindromic protein motif and modulated by dna binding. | expression of bacterial type ii toxin-antitoxin (ta) systems is regulated at the transcriptional level through direct binding of the antitoxin to pseudo-palindromic sequences on operator dna. in this context, the toxin functions as a co-repressor by stimulating dna binding through direct interaction with the antitoxin. here, we determine crystal structures of the complete 90 kda heterooctameric vapbc1 complex from caulobacter crescentus cb15 both in isolation and bound to its cognate dna operato ... | 2016 | 27998932 |
| structure and function of caulobacter crescentus aldose-aldose oxidoreductase. | aldose-aldose oxidoreductase (cc aaor) is a recently characterized enzyme from the bacterial strain caulobacter crescentus cb15 belonging to the glucose-fructose oxidoreductase/inositol dehydrogenase/rhizopine catabolism protein (gfo/idh/moca) family. cc aaor catalyses the oxidation and reduction of a panel of aldose monosaccharides using a tightly bound nadp(h) cofactor that is regenerated in the catalytic cycle. furthermore, cc aaor can also oxidize 1,4-linked oligosaccharides. in the present ... | 2015 | 26438878 |
| glucoamylase of caulobacter crescentus cb15: cloning and expression in escherichia coli and functional identification. | the biochemical properties of the maltodextrin-hydrolyzing enzymes of cold-tolerant proteobacterium caulobacter crescentus cb15 remain to be elucidated, although whose maltodextrin transport systems were well investigated. we cloned the putative glucoamylase of c. crescentus cb15 (cauloga) gene. the cauloga gene product that was expressed in e. coli was prone to forming inclusion bodies; however, most of the gene product was expressed in a soluble and active form when it was expressed as a fusio ... | 2014 | 24468405 |