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isolation of a thermophilic and halophilic tyrosol-degrading geobacillus from a tunisian high-temperature oil field.an aerobic, thermophilic, halotolerant and gram-positive bacterium, designated strain c5, was isolated from a high-temperature oil field, located in sfax, tunisia, after enrichment on tyrosol. strain c5 grew between 25 and 70 degrees c and optimally at 50 degrees c. it grew in the presence of 0-12% (w/v) nacl, with optimum growth at 3% (w/v) nacl. strain c5 was able to degrade tyrosol aerobically, in the presence of 30 g l(-1) nacl and under warm conditions (55 degrees c). the degradation of tyr ...200818399994
crystal structures of the 70-kda heat shock proteins in domain disjoining conformation.the 70-kda heat shock proteins (hsp70s) are highly conserved atp-dependent molecular chaperones composed of an n-terminal nucleotide binding domain (nbd) and a c-terminal protein substrate binding domain (sbd) in a bilobate structure. interdomain communication and nucleotide-dependent structural motions are critical for hsp70 chaperone functions. our understanding of these functions remains elusive due to insufficient structural information on intact hsp70s that represent the different states of ...200818400763
a large collapsed-state rna can exhibit simple exponential single-molecule dynamics.the process of large rna folding is believed to proceed from many collapsed structures to a unique functional structure requiring precise organization of nucleotides. the diversity of possible structures and stabilities of large rnas could result in non-exponential folding kinetics (e.g. stretched exponential) under conditions where the molecules have not achieved their native state. we describe a single-molecule fluorescence resonance energy transfer (fret) study of the collapsed-state region o ...200818402978
structural characterization of the acid-degraded secondary cell wall polymer of geobacillus stearothermophilus pv72/p2.the secondary cell wall polymer (scwp) from geobacillus stearothermophilus pv72/p2, which is involved in the anchoring of the surface-layer protein to the bacterial cell wall layer, is composed of 2-amino-2-deoxy- and 2-acetamido-2-deoxy-d-glucose, 2-acetamido-2-deoxy-d-mannose, and 2-acetamido-2-deoxy-d-mannuronic acid. the primary structure of the acid-degraded polysaccharide--liberated by hf-treatment from the cell wall--was determined by high-field nmr spectroscopy and mass spectrometry usin ...200818420185
production, purification, and characterization of a potential thermostable galactosidase for milk lactose hydrolysis from bacillus stearothermophilus.beta-galactosidase, commonly named lactase, is one of the most important enzymes used in dairy processing; it catalyzes the hydrolysis of lactose to its constituent monosaccharides glucose and galactose. here, a thermostable beta-galactosidase gene bgab from bacillus stearothermophilus was cloned and expressed in b. subtilis wb600. the recombinant enzyme was purified by a combination of heat treatment, ammonium sulfate fractionation, ion exchange, and gel filtration chromatography techniques. th ...200818420605
genome classification by gene distribution: an overlapping subspace clustering approach.genomes of lower organisms have been observed with a large amount of horizontal gene transfers, which cause difficulties in their evolutionary study. bacteriophage genomes are a typical example. one recent approach that addresses this problem is the unsupervised clustering of genomes based on gene order and genome position, which helps to reveal species relationships that may not be apparent from traditional phylogenetic methods.200818430250
heterologous expression of the alcohol dehydrogenase (adhi) gene from geobacillus thermoglucosidasius strain m10exg.a thermostable alcohol dehydrogenase (adh-i) isolated from the potential thermophilic ethanologen geobacillus thermoglucosidasius strain m10exg has been characterised. inverse pcr showed that the gene (adhi) was localised with 3-hexulose-6-phosphate synthase (hps) and 6-phospho-3 hexuloisomerase (phi) on its genome. the deduced peptide sequence of the 1020-bp m10exg adhi, which corresponds to 340 amino acids, shows 96% and 89% similarity to adh-ht and adh-t from geobacillus stearothermophilus st ...200818436321
the cold-active lip1 lipase from the antarctic bacterium pseudoalteromonas haloplanktis tac125 is a member of a new bacterial lipolytic enzyme family.the genome of the antarctic bacterium pseudoalteromonas haloplanktis tac125 was searched for the presence of genes encoding ester-hydrolysing enzymes. amongst the others, the gene pshaa0051 coding for a putative secreted esterase/lipase was selected. the psychrophilic gene was cloned, functionally over-expressed in p. haloplanktis tac125, and the recombinant product (after named phtac125 lip1) was purified. phtac125 lip1 was found to be associated to the outer membrane and exhibited higher enzym ...200818437283
cloning, sequencing and analysis of dnak -dnaj gene cluster of bacillus megaterium.the dna fragment of heat shock genes (hrca-grpe-dnak-dnaj) containing complete hrca-grpe-dnak operon and the transcription unit of dnaj was cloned, sequensed and analyzed from bacillus megaterium rf5. the sequence of hrca, grpe and dnaj were first time reported, and their coding products exibit 60%, 63% and 81% of identities to the homologs of b. subtilis. a sigmaa-type promoter of gram-positive bacteria (pa1) and a terminator were located upstream of the hrca and downstream of dnak, and a contr ...200818785662
the structure of yqeh. an atnos1/atnoa1 ortholog that couples gtp hydrolysis to molecular recognition.atnos1/atnoa1 was identified as a nitric oxide-generating enzyme in plants, but that function has recently been questioned. to resolve issues surrounding atnoa1 activity, we report the biochemical properties and a 2.36 a resolution crystal structure of a bacterial atnoa1 ortholog (yqeh). geobacillus yqeh fused to a putative atnoa1 leader peptide complements growth and morphological defects of atnoa1 mutant plants. yqeh does not synthesize nitric oxide from l-arginine but rather hydrolyzes gtp. t ...200818801747
thermostability and molecular encapsulation within an engineered caged protein scaffold.self-assembling biological complexes such as viral capsids have been manipulated to function in innovative nanotechnology applications. the e2 component of pyruvate dehydrogenase from bacillus stearothermophilus forms a dodecahedral complex and potentially provides another platform for these purposes. in this investigation, we show that this protein assembly exhibits unusual stability and can be modified to encapsulate model drug molecules. to distill the e2 protein down to its structural scaffo ...200818814295
single-molecule nonequilibrium periodic mg2+-concentration jump experiments reveal details of the early folding pathways of a large rna.the evolution of rna conformation with mg(2+) concentration ([mg(2+)]) is typically determined from equilibrium titration measurements or nonequilibrium single [mg(2+)]-jump measurements. we study the folding of single rna molecules in response to a series of periodic [mg(2+)] jumps. the 260-residue catalytic domain of rnase p rna from bacillus stearothermophilus is immobilized in a microfluidic flow chamber, and the rna conformational changes are probed by fluorescence resonance energy transfer ...200818448679
pilot-scale experimental and theoretical investigations into the thermal destruction of a bacillus anthracis surrogate embedded in building decontamination residue bundles.bacillus anthracis (b. anthracis) spores were released through the u.s. mail system in 2001, highlighting the need to develop efficacious methods of decontaminating and disposing of materials contaminated with biological agents. incineration of building decontamination residue is a disposal option for such material, although the complete inactivation of bacterial spores via this technique is not a certainty. tests revealed that under some circumstances, geobacillus stearothermophilus (g. stearot ...200818754498
the family 52 beta-xylosidase from geobacillus stearothermophilus is a dimer: structural and biophysical characterization of a glycoside hydrolase.xylans are the most abundant polysaccharides forming the plant cell wall hemicelluloses, and they are degraded, among other proteins, by beta-xylosidase enzymes. in this work, the structural and biophysical properties of the family 52 beta-xylosidase from geobacillus stearothermophilus, xynb2, are described. size exclusion chromatography, analytical centrifugation, itc, cd, fluorescence (steady state and ans-binding) and ftir were used to obtain the structure, the oligomerization state and the c ...200818657634
[synthesis of 2-chloro-2'-deoxyadenosine by microbiological transglycosylation using a recombinant escherichia coli strain].cladribine (2-chloro-2'-deoxyadenosine) was synthesized using intact cells of the recombinant escherichia coli strain producing geobacillus stearothermophilus b-2194 thermostable purine-nucleoside phosphorylase ii (ec 2.4.2.1). use of the cells containing this thermostable enzyme allowed the process to be conducted at a temperature of 70 degrees c, which provided the maximal concentrations of sparingly soluble substrates. the best results were obtained with 2-chloroadenine as a modified base. th ...200818669260
the dihydrolipoamide dehydrogenase of aeromonas caviae st exhibits nadh-dependent tellurite reductase activity.potassium tellurite (k(2)teo(3)) is extremely toxic for most forms of life and only a limited number of organisms are naturally resistant to the toxic effects of this compound. crude extracts prepared from the environmental isolate aeromonas caviae st catalize the in vitro reduction of teo32- in a nadh-dependent reaction. upon fractionation by ionic exchange column chromatography three major polypeptides identified as the e1, e2, and e3 components of the pyruvate dehydrogenase (pdh) complex were ...200818675788
substrate-induced conformational changes of the truncated catalytic domain of geobacillus stearothermophilus lysyl-trna synthetase as examined by fluorescence.the substrate-induced conformational change of the truncated c-terminal catalytic domain (cat) of geobacillus stearothermophilus lysyl-trna synthetase was examined by measuring tryptophan fluorescence of the truncated cat domain in the presence or absence of the truncated n-terminal trna anticodon-binding domain (tab). the fluorescence spectrum of cat was not changed by the addition of l-lysine or atp, whereas the intensity increased by adding a lysyl-adenylate analogue, suggesting that the cat ...200818675944
rloc: a wobble nucleotide-excising and zinc-responsive bacterial trnase.summary: the conserved bacterial protein rloc, a distant homologue of the trna(lys) anticodon nuclease (acnase) prrc, is shown here to act as a wobble nucleotide-excising and zn(++)-responsive trnase. the more familiar prrc is silenced by a genetically linked type i dna restriction-modification (r-m) enzyme, activated by a phage anti-dna restriction factor and counteracted by phage trna repair enzymes. rloc shares prrc's abc atpase motifs and catalytic acnase triad but features a distinct zinc-h ...200818681940
the structure and binding behavior of the bacterial cell surface layer protein sbsc.surface layers (s-layers) comprise the outermost cell envelope component of most archaea and many bacteria. here we present the structure of the bacterial s-layer protein sbsc from geobacillus stearothermophilus, showing a very elongated and flexible molecule, with strong and specific binding to the secondary cell wall polymer (scwp). the crystal structure of rsbsc((31-844)) revealed a novel fold, consisting of six separate domains, which are connected by short flexible linkers. the n-terminal d ...200818682224
non-selective toxicological effects of the insect juvenile hormone analogue methoprene. a membrane biophysical approach.the gram-positive bacterium, bacillus stearothermophilus, was used as a model organism to identify the non-selective toxic effects of the currently used insecticide methoprene (isopropyl(2e,4e)-11-methoxy-3,7,11-trimethyl-2,4-dodecadienoate). a significant decrease of the yield of bacterial cultures and a premature appearance of ultrastructural abnormalities in cells cultured in the presence of the insecticide were taken as indicators of cytotoxicity. a putative correlation of this cytotoxicity ...200818682901
importance of tyrosine residues of bacillus stearothermophilus serine hydroxymethyltransferase in cofactor binding and l-allo-thr cleavage.serine hydroxymethyltransferase (shmt) from bacillus stearothermophilus (bsshmt) is a pyridoxal 5'-phosphate-dependent enzyme that catalyses the conversion of l-serine and tetrahydrofolate to glycine and 5,10-methylene tetrahydrofolate. in addition, the enzyme catalyses the tetrahydrofolate-independent cleavage of 3-hydroxy amino acids and transamination. in this article, we have examined the mechanism of the tetrahydrofolate-independent cleavage of 3-hydroxy amino acids by shmt. the three-dimen ...200818699779
recovery of spores from thermophilic dairy bacilli and effects of their surface characteristics on attachment to different surfaces.spores from four geobacillus spp. were isolated from a milk powder manufacturing line in new zealand. liquid sporulation media produced spore yields of approximately 10(7) spores ml(-1); spores were purified using a two-phase system created with polyethylene glycol 4000 and 3 m phosphate buffer. the zeta potentials of the spores from the four isolates ranged from -10 to -20 mv at neutral ph, with an isoelectric point between ph 3 and 4. through contact angle measurements, spores were found to be ...200818083853
site-specific incorporation of keto amino acids into functional g protein-coupled receptors using unnatural amino acid mutagenesis.g protein-coupled receptors (gpcrs) are ubiquitous heptahelical transmembrane proteins involved in a wide variety of signaling pathways. the work described here on application of unnatural amino acid mutagenesis to two gpcrs, the chemokine receptor ccr5 (a major co-receptor for the human immunodeficiency virus) and rhodopsin (the visual photoreceptor), adds a new dimension to studies of gpcrs. we incorporated the unnatural amino acids p-acetyl-l-phenylalanine (acp) and p-benzoyl-l-phenylalanine ...200817993461
cyclomaltodextrin glucanotransferase-catalyzed transglycosylation from dextrin to alkanol maltosides.maltosides of butanol, octanol, and lauryl alcohol were found for the first time to serve as substrates for cyclomaltodextrin glucanotransferase (cgtase), and glycosyl residue was transfered from dextrin to the substrate affording novel maltosides with 3-4 glucose units.200818997431
characterization of thermophilic bacteria using surface-enhanced raman scattering.surface-enhanced raman scattering (sers) can provide molecular-level information about the molecules and molecular structures in the vicinity of nanostructured noble metal surfaces such as gold and silver. the three thermophilic bacteria bacillus licheniformis, geobacillus stearothermophilus, and geobacillus pallidus, a gram-negative bacterium e. coli, and a gram-positive bacterium b. megaterium are comparatively characterized using sers. the sers spectra of thermophilic bacteria are similar, wh ...200819007464
isolation of the phe-operon from g. stearothermophilus comprising the phenol degradative meta-pathway genes and a novel transcriptional regulator.geobacillus stearothermophilus is able to utilize phenol as a sole carbon source. a dna fragment encoding a phenol hydroxylase catalyzing the first step in the meta-pathway has been isolated previously. based on these findings a pcr-based dna walk was performed initially to isolate a catechol 2,3-dioxygenase for biosensoric applications but was continued to elucidate the organisation of the genes encoding the proteins for the metabolization of phenol.200819014555
recombinant glycans on an s-layer self-assembly protein: a new dimension for nanopatterned biomaterials.crucial biological phenomena are mediated through carbohydrates that are displayed in a defined manner and interact with molecular scale precision. we lay the groundwork for the integration of recombinant carbohydrates into a "biomolecular construction kit" for the design of new biomaterials, by utilizing the self-assembly system of the crystalline cell surface (s)-layer protein sgse of geobacillus stearothermophilus nrs 2004/3a. sgse is a naturally o-glycosylated protein, with intrinsic propert ...200818816436
production and characterization of a mesophilic lipase isolated from bacillus stearothermophilus ab-1.using bacillus stearothermophilus ab-1 isolated from air, the production of lipase was attempted along with its purification and characterization studies. when different carbon and nitrogen sources were supplemented in the culture medium, xylose, tryptophan, alanine, phenylalanine and potassium nitrate were found to be the best. during cultivation, the strain secreted most of its lipase content after 48 h. in particular, the lipase produced in the culture broth showed 300 u ml(-1) when cultivate ...200818819547
potent alpha-glucosidase inhibitors purified from the red alga grateloupia elliptica.diabetes mellitus is a most serious and chronic disease whose incidence rates are increasing with incidences of obesity and aging of the general population over the world. one therapeutic approach for decreasing postprandial hyperglycemia is to retard absorption of glucose by inhibition of alpha-glucosidase. two bromophenols, 2,4,6-tribromophenol and 2,4-dibromophenol, were purified from the red alga grateloupia elliptica. ic(50) values of 2,4,6-tribromophenol and 2,4-dibromophenol were 60.3 and ...200818951591
substrate-ligand interactions in geobacillus stearothermophilus nitric oxide synthase.nitric oxide synthase (nos) generates no via a sequential two-step reaction [l-arginine (l-arg) --> n-hydroxy-l-arginine (noha) --> l-citrulline + no]. each step of the reaction follows a distinct mechanism defined by the chemical environment introduced by each substrate bound to the heme active site. the dioxygen complex of the nos enzyme from a thermophilic bacterium, geobacillus stearothermophilus (gsnos), is unusually stable; hence, it provides a unique model for the studies of the mechanist ...200818956884
translation initiation factor if1 of bacillus stearothermophilus and thermus thermophilus substitute for escherichia coli if1 in vivo and in vitro without a direct if1-if2 interaction.bacterial translation initiation factor if1 is homologous to archaeal aif1a and eukaryal eif1a, which form a complex with their homologous if2-like factors (aif5b and eif5b respectively) during initiation of protein synthesis. a similar if1-if2 interaction is assumed to occur in all bacteria and supported by cross-linking data and stabilization of the 30s-if2 interaction by if1. here we compare escherichia coli if1 with thermophilic factors from bacillus stearothermophilus and thermus thermophil ...200818976282
improved thermostability and acetic acid tolerance of escherichia coli via directed evolution of homoserine o-succinyltransferase.in escherichia coli, growth is limited at elevated temperatures mainly because of the instability of a single enzyme, homoserine o-succinyltransferase (meta), the first enzyme in the methionine biosynthesis pathway. the meta gene from the thermophile geobacillus kaustophilus cloned into the e. coli chromosome was found to enhance the growth of the host strain at elevated temperature (44 degrees c), thus confirming the limited growth of e. coli due to meta instability. in order to improve e. coli ...200818978085
the nos gene cluster from gram-positive bacterium geobacillus thermodenitrificans ng80-2 and functional characterization of the recombinant nosz.the nos gene cluster encoding the activity of nitrous oxide reductase (n2or) for the final step of the denitrification pathway has been well studied in gram-negative bacteria. our previous study on the genome of geobacillus thermodenitrificans ng80-2 revealed the presence of the nos gene cluster in this gram-positive bacterium. in this follow-up study, the nos gene cluster of g. thermodenitrificans ng80-2 was further analyzed and compared with those of other origins. the structural gene nosz was ...200819054093
structures of the human pyruvate dehydrogenase complex cores: a highly conserved catalytic center with flexible n-terminal domains.dihydrolipoyl acetyltransferase (e2) is the central component of pyruvate dehydrogenase complex (pdc), which converts pyruvate to acetyl-coa. structural comparison by cryo-electron microscopy (cryo-em) of the human full-length and truncated e2 (te2) cores revealed flexible linkers emanating from the edges of trimers of the internal catalytic domains. using the secondary structure constraints revealed in our 8 a cryo-em reconstruction and the prokaryotic te2 atomic structure as a template, we der ...200818184588
thermophilic bacteria in cool temperate soils: are they metabolically active or continually added by global atmospheric transport?thermophilic soil geobacilli isolated from cool temperate geographical zone environments have been shown to be metabolically inactive under aerobic conditions at ambient temperatures (-5 to 25 degrees c). it is now confirmed that a similar situation exists for their anaerobic denitrification activity. it is necessary therefore to determine the mechanisms that sustain the observed significant viable populations in these soils. population analysis of thermophiles in rainwater and air samples has s ...200818256821
off-pathway, oxygen-dependent thiamine radical in the krebs cycle.the catalytic cofactor thiamine diphosphate is found in many enzymes of central metabolism and is essential in all extant forms of life. we demonstrate the presence of an oxygen-dependent free radical in the thiamine diphosphate-dependent escherichia coli 2-oxoglutarate dehydrogenase, which is a key component of the tricarboxylic acid (krebs) cycle. the radical was sufficiently long-lived to be trapped by freezing in liquid nitrogen, and its electronic structure was investigated by electron para ...200818183975
snapshots of catalysis in the e1 subunit of the pyruvate dehydrogenase multienzyme complex.the pyruvate dehydrogenase multienzyme assembly (pdh) generates acetyl coenzyme a and reducing equivalents from pyruvate in a multiple-step process that is a nexus of central metabolism. we report crystal structures of the geobacillus stearothermophilus pdh e1p subunit with ligands that mimic the prereaction complex and the postdecarboxylation product. the structures implicate residues that help to orient substrates, nurture intermediates, and organize surface loops so that they can engage a mob ...200819081062
antioxidant activity of biotransformed sex hormones facilitated by bacillus stearothermophilus.bacillus stearothermophilus, a thermophilic bacterium isolated from kuwaiti desert, when incubated with exogenous progesterone for 10 days at 65 degrees c produced two monohydroxylated, two dihydroxy isomers of progesterone and a b-seco compound. these metabolites were purified by tlc and hplc followed by their identification through (1)h, (13)c nmr and other spectroscopic data. microbial hydroxylation of 17beta-estradiol resulted in the production of estrone. the effect of some inducers resulte ...200819082955
cloning, expression, and characterization of a thermostable pap2l2, a new member of the type-2 phosphatidic acid phosphatase family from geobacillus toebii t-85.most members of the type-2 phosphatidic acid phosphatase (pap2) superfamily are integral membrane phophatases involved in lipid-related signal transduction and metabolism. here we describe the cloning of a novel gene from geobacillus toebii t-85, encoding a pap2-like protein, gtb pap2l2, which contains 212 amino acids and shows a limited homology to other known pap2s, especially at conserved phosphatase motifs, and a similar six-transmembrane topology structure. this enzyme was expressed, and pu ...200819060391
a modeling study by response surface methodology and artificial neural network on culture parameters optimization for thermostable lipase production from a newly isolated thermophilic geobacillus sp. strain arm.thermostable bacterial lipases occupy a place of prominence among biocatalysts owing to their novel, multifold applications and resistance to high temperature and other operational conditions. the capability of lipases to catalyze a variety of novel reactions in both aqueous and nonaqueous media presents a fascinating field for research, creating interest to isolate novel lipase producers and optimize lipase production. the most important stages in a biological process are modeling and optimizat ...200819105837
structure of polc reveals unique dna binding and fidelity determinants.polc is the polymerase responsible for genome duplication in many gram-positive bacteria and represents an attractive target for antibacterial development. we have determined the 2.4-a resolution crystal structure of geobacillus kaustophilus polc in a ternary complex with dna and dgtp. the structure reveals nascent base pair interactions that lead to highly accurate nucleotide incorporation. a unique beta-strand motif in the polc thumb domain contacts the minor groove, allowing replication error ...200819106298
characterization of a lysin from deep-sea thermophilic bacteriophage gve2.thermostable enzymes from thermophiles have attracted extensive studies. however, little is known about thermophilic lysin of bacteriophage obtained from deep-sea hydrothermal vent. in this study, a lysin from deep-sea thermophilic bacteriophage geobacillus virus e2 (gve2) was characterized for the first time. it was found that the gve2 lysin was highly homologous with n-acetylmuramoyl-l-alanine amidases. after expression in escherichia coli, the recombinant gve2 lysin was purified. the recombin ...200818224315
molecular dynamics study of the structure, flexibility and dynamics of thermostable l1 lipase at high temperatures.molecular dynamics (md) simulations have been used to understand how protein structure, dynamics, and flexibility are affected by adaptation to high temperature for several years. we report here the results of the high temperature md simulations of bacillus stearothermophilus l1 (l1 lipase). we found that the n-terminal moiety of the enzyme showed a high flexibility and dynamics during high temperature simulations which preceded and followed by clear structural changes in two specific regions; t ...200919130194
kinetics of deoxy-ctp incorporation opposite a dg-c8-n-2-aminofluorene adduct by a high-fidelity dna polymerase.the model carcinogen n-2-acetylaminofluorene covalently binds to the c8 position of guanine to form two adducts, the n-(2'-deoxyguanosine-8-yl)-aminofluorene (g-af) and the n-2-(2'-deoxyguanosine-8-yl)-acetylaminofluorene (g-aaf). although they are chemically closely related, their biological effects are strongly different and they are processed by different damage tolerance pathways. g-af is bypassed by replicative and high-fidelity polymerases, while specialized polymerases ensure synthesis pa ...200919150355
cloning, purification and characterization of geobacillus stearothermophilus v uroporphyrinogen-iii c-methyltransferase: evaluation of its role in resistance to potassium tellurite in escherichia coli.the geobacillus stearothermophilus v coba gene encoding uroporphyrinogen-iii c-methyltransferase (also referred to as sumt) was cloned into escherichia coli and the recombinant enzyme was overexpressed and purified to homogeneity. the enzyme binds s-adenosyl-l-methionine and catalyzes the production of iii methyl uroporphyrinogen in vitro. e. coli cells expressing the g. stearothermophilus v coba gene exhibited increased resistance to potassium tellurite and potassium tellurate. site-directed mu ...200919154787
immobilization of recombinant thermostable beta-galactosidase from bacillus stearothermophilus for lactose hydrolysis in milk.a recombinant thermostable beta-galactosidase from bacillus stearothermophilus was immobilized onto chitosan using tris(hydroxymethyl)phosphine (thp) and glutaraldehyde, and a packed bed reactor was utilized to hydrolyze lactose in milk. the thermostability and enzyme activity of thp-immobilized beta-galactosidase during storage was superior to that of free and glutaraldehyde-immobilized enzymes. the thp-immobilized beta-galactosidase showed greater relative activity in the presence of ca(2+) th ...200919164659
heavy metal resistance of some thermophiles: potential use of alpha-amylase from anoxybacillus amylolyticus as a microbial enzymatic bioassay.six thermophilic extremophiles, anoxybacillus amylolyticus, geobacillus thermoleovorans, geobacillus thermoleovorans subspecies stromboliensis, geobacillus toebii subspecies decanicus, bacillus thermantarcticus and thermus oshimai, isolated from different environmental sites, were studied for their heavy metal resistance. the effects of heavy metals on microorganism growth were studied here in a pilot fermenter tank spiked with various trace metals, (ni(2+), zn(2+), co(2+), hg(2+), mn(2+), cr(6+ ...200919070660
independent saturation of three trprs subsites generates a partially assembled state similar to those observed in molecular simulations.two new crystal structures of bacillus stearothermophilus tryptophanyl-trna synthetase (trprs) afford evidence that a closed interdomain hinge angle requires a covalent bond between amp and an occupant of either pyrophosphate or tryptophan subsite. they also are within experimental error of a cluster of structures observed in a nonequilibrium molecular dynamics simulation showing partial active-site assembly. further, the highest energy structure in a minimum action pathway computed by using ela ...200919174517
two crystal structures of lysyl-trna synthetase from bacillus stearothermophilus in complex with lysyladenylate-like compounds: insights into the irreversible formation of the enzyme-bound adenylate of l-lysine hydroxamate.aminoacyl-trna synthetase forms an enzyme-bound intermediate, aminoacyladenylate in the amino-acid activation reaction. this reaction is monitored by measuring the atp-ppi exchange reason in which [(32)p]ppi is incorporated into atp. we previously reported that l-lysine hydroxamate completely inhibited the l-lysine-dependent atp-ppi exchange reaction catalysed by lysyl-trna synthetase from bacillus stearothermophilus (bslysrs). several experiments suggested that bslysrs can adenylate l-lysine hy ...200919174549
isolation and characterization of cellulose-degrading bacteria from the deep subsurface of the homestake gold mine, lead, south dakota, usa.the present study investigated the cultivable mesophilic (37 degrees c) and thermophilic (60 degrees c) cellulose-degrading bacterial diversity in a weathered soil-like sample collected from the deep subsurface (1.5 km depth) of the homestake gold mine in lead, south dakota, usa. chemical characterization of the sample by x-ray fluorescence spectroscopy revealed a high amount of toxic heavy metals such as cu, cr, pb, ni, and zn. molecular community structures were determined by phylogenetic anal ...200919189143
thermodynamic analysis reveals a temperature-dependent change in the catalytic mechanism of bacillus stearothermophilus tyrosyl-trna synthetase.catalysis of trna(tyr) aminoacylation by tyrosyl-trna synthetase can be divided into two steps. in the first step, tyrosine is activated by atp to form the tyrosyl-adenylate intermediate. in the second step, the tyrosyl moiety is transferred to the 3' end of trna. to investigate the roles that enthalpic and entropic contributions play in catalysis by bacillus stearothermophilus tyrosyl-trna synthetase (tyrrs), the temperature dependence for the activation of tyrosine and subsequent transfer to t ...200919098308
evaluation of a microbiological multi-residue system on the detection of antibacterial substances in ewe milk.to protect both, public health and the dairy industry, from the presence of antibiotic residues in milk, control programmes have been established, which include the needed screening tests. this work focuses on the application of a microbiological multi-residue system in ewe milk, a method based on the use of six different plates, each seeded with one of the following bacteria: geobacillus stearothermophilus var. calidolactis (beta-lactams), bacillus subtilis at ph 8.0 (aminoglycosides), kocuria ...200919100896
how to switch off a histidine kinase: crystal structure of geobacillus stearothermophilus kinb with the inhibitor sda.entry to sporulation in bacilli is governed by a histidine kinase phosphorelay, a variation of the predominant signal transduction mechanism in prokaryotes. sda directly inhibits sporulation histidine kinases in response to dna damage and replication defects. we determined a 2.0-a-resolution x-ray crystal structure of the intact cytoplasmic catalytic core [comprising the dimerization and histidine phosphotransfer domain (dhp domain), connected to the atp binding catalytic domain] of the geobacil ...200919101565
identification of new secreted proteins and secretion of heterologous amylase by c. glutamicum.in this study, secreted corynebacterium glutamicum proteins were investigated by two-dimensional gel electrophoresis. around 100 spots observed in the ph range 4.5-5.5 had molecular masses that varied from 10 to 50 kda. upon n-terminal amino acid sequence analysis by edman degradation, two of them were hits to two hypothetical proteins encoded by cgr_1176 and cgr_2070 on c. glutamicum r genome, respectively. active-form alpha-amylase derived from geobacillus stearothermophilus was successfully s ...200919066885
activation of bacterial thermoalkalophilic lipases is spurred by dramatic structural rearrangements.the bacterial thermoalkalophilic lipases that hydrolyze saturated fatty acids at 60-75 degrees c and ph 8-10 are grouped as the lipase family i.5. we report here the crystal structure of the lipase from geobacillus thermocatenulatus, the first structure of a member of the lipase family i.5 showing an open configuration. unexpectedly, enzyme activation involves large structural rearrangements of around 70 amino acids and the concerted movement of two lids, the alpha6- and alpha7-helices, unmaskin ...200919056729
engineering a reversible, high-affinity system for efficient protein purification based on the cohesin-dockerin interaction.efficient degradation of cellulose by the anaerobic thermophilic bacterium, clostridium thermocellum, is carried out by the multi-enzyme cellulosome complex. the enzymes on the complex are attached in a calcium-dependent manner via their dockerin (doc) module to a cohesin (coh) module of the cellulosomal scaffoldin subunit. in this study, we have optimized the coh-doc interaction for the purpose of protein affinity purification. a c. thermocellum coh module was thus fused to a carbohydrate-bindi ...200918979459
characterization of bacillus stearothermophilus infa and of its product if1.bacillus stearothermophilus infa encoding translation initiation factor if1 was cloned and expressed in escherichia coli and its transcript and protein product characterized. although the functional properties of b. stearothermophilus and e. coli if1, compared in several translational tests in the presence of both homologous and heterologous components, are not entirely identical, the two proteins are interchangeable in an in vitro translational system programmed with a natural mrna. the availab ...200918951960
engineering of the alpha-amylase from geobacillus stearothermophilus us100 for detergent incorporation.amyus100deltaig is a variant of the most thermoactive and thermostable maltohexaose forming alpha-amylase produced by geobacillus stearothermophilus sp.us100. this enzyme which was designed to improve the thermostability of the wild-type enzyme has acquired a very high resistance to chelator agents. according to modeling structural studies and with the aim of enhancing its resistance towards chemical oxidation, a mutant (amyus100deltaig/m197a) was created by substituting methionine 197 to alanin ...200918951544
characterization and identification of geobacillus spp. isolated from soldhar hot spring site of garhwal himalaya, india.13 morphologically distinct strains of thermophilic bacteria isolated from a hot spring site in garhwal region of indian himalaya have been characterized and identified using phenotypic and genotypic characters. all the strains developed circular to irregular colonies between 2-3 mm on tryptone yeast extract (ty) agar plates at 65 degrees c following 24-36 h incubation. in ty broth, facultative bacterial growth was observed within 12-16 h of incubation at 65 degrees c. the bacterial strains coul ...200919025872
structural and functional studies of bacillus stearothermophilus serine hydroxymethyltransferase: the role of asn(341), tyr(60) and phe(351) in tetrahydrofolate binding.shmt (serine hydoxymethyltransferase), a type i pyridoxal 5'-phosphate-dependent enzyme, catalyses the conversion of l-serine and thf (tetrahydrofolate) into glycine and 5,10-methylene thf. shmt also catalyses several thf-independent side reactions such as cleavage of beta-hydroxy amino acids, transamination, racemization and decarboxylation. in the present study, the residues asn(341), tyr(60) and phe(351), which are likely to influence thf binding, were mutated to alanine, alanine and glycine ...200919046138
purification and characterization of a glycoside hydrolase family 43 beta-xylosidase from geobacillus thermoleovorans it-08.the gene encoding a glycoside hydrolase family 43 beta-xylosidase (gbtxyl43a) from the thermophilic bacterium geobacillus thermoleovorans strain it-08 was synthesized and cloned with a c-terminal his-tag into a pet29b expression vector. the recombinant gene product termed gbtxyl43a was expressed in escherichia coli and purified to apparent homogeneity. michaelis-menten kinetic parameters were obtained for the artificial substrates p-nitrophenyl-beta-d: -xylopyranose (4npx) and p-nitrophenyl-alph ...200918815904
screening and distributing features of bacteria with hydantoinase and carbamoylase.hydantoinase and carbamoylase are key biocatalysts for the production of optically pure amino acids from dl-5-substituted hydantoins (ssh). out of 364 isolated strains with hydantoinase and carbamoylase at 45 degrees c, 24 strains showed efficient hydantoinase and carbamoylase activities. among them, 17 produced l-amino acids, and 7 produced d-amino acids from both aromatic dl-5-benzylhydantoin and aliphatic dl-5-isopropylhydantoin. most of the strains that were able to form l-amino acid belonge ...200917498938
functional analysis of the thermophilic denitrifying bacterium geobacillus sp. strain tdn01 in continuous culture.the thermophilic denitrifying bacterium geobacillus sp. strain tdn01 was examined to determine the effects of nitrogen and carbon sources and nitrate and nitrite concentrations on denitrification in a batch culture. the specific nitrate removal rate was 12 times higher with ammonia than without ammonia. the consumption rates of nitrate and succinate were proportional. furthermore, the growth rates with 120 and 150 mm nitrate were only slightly lower than those with 60 mm and did not cause notabl ...200919436125
bayesian model averaging for ligand discovery.high-throughput screening (hts) is now a standard approach used in the pharmaceutical industry to identify potential drug-like lead molecules. the analysis linking biological data with molecular properties is a major goal in both academic and pharmaceutical research. this paper presents a bayesian analysis of high-dimensional descriptor data using markov chain monte carlo (mcmc) simulations for learning classification trees as a novel method for pharmacophore and ligand discovery. we use experim ...200919489531
structure and conformational stability of a tetrameric thermostable n-succinylamino acid racemase.the n-succinylamino acid racemases (nsaar) belong to the enolase superfamily and they are large homooctameric/hexameric species that require a divalent metal ion for activity. we describe the structure and stability of nsaar from geobacillus kaustophilus (gknsaar) in the absence and in the presence of co(2+) by using hydrodynamic and spectroscopic techniques. the co(2+), among other assayed divalent ions, provides the maximal enzymatic activity at physiological ph. the protein seems to be a tetr ...200919517534
ambivalent incorporation of the fluorescent cytosine analogues tc and tco by human dna polymerase alpha and klenow fragment.we studied the incorporation of the fluorescent cytidine analogues 1,3-diaza-2-oxophenothiazine (tc) and 1,3-diaza-2-oxophenoxazine (tco) by human dna polymerase alpha and klenow fragment of dna polymerase i (escherichia coli). these tricyclic nucleobases possess the regular hydrogen bonding interface of cytosine but are significantly expanded in size toward the major groove. despite the size alteration, both dna polymerases insert dtctp and dtcotp with remarkable catalytic efficiency. polymeriz ...200919580325
bhargavaea cecembensis gen. nov., sp. nov., isolated from the chagos-laccadive ridge system in the indian ocean.a novel gram-positive, rod-shaped, non-motile, non-spore-forming bacterium, strain dse10(t), was isolated from a deep-sea sediment sample collected at a depth of 5904 m from the chagos-laccadive ridge system in the indian ocean. cells of strain dse10(t) were positive for catalase, oxidase, urease and lipase activities and contained iso-c(14 : 0), iso-c(15 : 0), iso-c(16 : 0) and anteiso-c(15 : 0) as the major fatty acids. the major respiratory quinones were mk-6 and mk-8 and the major lipids wer ...200919625444
the atpase cycle of pcra helicase and its coupling to translocation on dna.the superfamily 1 bacterial helicase pcra has a role in the replication of certain plasmids, acting with the initiator protein (repd) that binds to and nicks the double-stranded origin of replication. pcra also translocates single-stranded dna with discrete steps of one base per atp hydrolyzed. individual rate constants have been determined for the dna helicase pcra atpase cycle when bound to either single-stranded dna or a double-stranded dna junction that also has repd bound. the fluorescent a ...200919647000
falsibacillus pallidus to replace the homonym bacillus pallidus zhou et al. 2008.the prokaryotic species name bacillus pallidus zhou et al. 2008 is illegitimate because it is a later homonym of the name bacillus pallidus scholz et al. 1988 (bacteria, firmicutes, bacillales, bacillaceae, bacillus). although bacillus pallidus scholz et al. 1988 was transferred to the genus geobacillus as geobacillus pallidus comb. nov. in 2004, the species name bacillus pallidus scholz et al. 1988 remains validly published and has priority at that position [principle 8 of the bacteriological c ...200919767356
two novel metal-independent long-chain alkyl alcohol dehydrogenases from geobacillus thermodenitrificans ng80-2.two alkyl alcohol dehydrogenase (adh) genes from the long-chain alkane-degrading strain geobacillus thermodenitrificans ng80-2 were characterized in vitro. adh1 and adh2 were prepared heterologously in escherichia coli as a homooctameric and a homodimeric protein, respectively. both adhs can oxidize a broad range of alkyl alcohols up to at least c(30), as well as 1,3-propanediol and acetaldehyde. adh1 also oxidizes glycerol, and adh2 oxidizes isopropyl alcohol, isoamylol, acetone, octanal and de ...200919383697
l-ribose production from l-arabinose by using purified l-arabinose isomerase and mannose-6-phosphate isomerase from geobacillus thermodenitrificans.two enzymes, l-arabinose isomerase and mannose-6-phosphate isomerase, from geobacillus thermodenitrificans produced 118 g/liter l-ribose from 500 g/liter l-arabinose at ph 7.0, 70 degrees c, and 1 mm co(2+) for 3 h, with a conversion yield of 23.6% and a volumetric productivity of 39.3 g liter(-1) h(-1).200919749063
one-plasmid tunable coexpression for mycobacterial protein-protein interaction studies.a single plasmid that allows controlled coexpression has been developed for use in mycobacteria. the tetracycline inducible promoter, pteto, was used to provide tetracycline-dependent induction of one gene, while the psmyc, pimyc, or phsp promoters were used to provide three different levels of constitutive expression of a second gene. the functions of these four individual promoters were established using green fluorescent protein (gfp) and a newly identified red fluorescence inducible protein ...200919760663
restoring 3'-5' exonuclease activity of thermophilic geobacillus dna polymerase i using site-directed mutagenesis in active site.three-dimensional structure and alignment analyses of 3'-5' exonuclease domain of dna polymerase i from thermophilic geobacillus sp. mkk show that the key catalytic amino acids in 3'-5' exonuclease domain are changed and the enzyme looses the activity. in order to render the activity, a catalytic module is constructed in the active site using site-directed mutagenesis. seven mutant clones of the enzyme are generated containing: m1 (v319d, e325l), m2 (a376d), m3 (d425f), m4 (insy446, k450d), m12 ...200919770007
functional roles of a structural element involving na+-pi interactions in the catalytic site of t1 lipase revealed by molecular dynamics simulations.interactions between metal ions and pi systems (metal-pi interactions) are known to confer significant stabilization energy. however, in biological systems, few structures with metal-pi coordination have been determined; thus, its roles must still be elucidated. the cation-pi interactions are not correctly described by current molecular mechanics even when using a polarizable force field, and thus they require quantum mechanical calculations for accurate estimation. however, the huge computation ...200919886661
deciphering the flexibility and dynamics of geobacillus zalihae strain t1 lipase at high temperatures by molecular dynamics simulation.the stability of biocatalysts is an important criterion for a sustainable industrial operation economically. t1 lipase is a thermoalkalophilic enzyme derived from geobacillus zalihae strain t1 (t1 lipase) that was isolated from palm oil mill effluent (pome) in malaysia. we report here the results of high temperatures molecular dynamics (md) simulations of t1 lipase in explicit solvent. we found that the n-terminal moiety of this enzyme was accompanied by a large flexibility and dynamics during t ...200920001926
crystal structures of leishmania mexicana phosphoglycerate mutase suggest a one-metal mechanism and a new enzyme subclass.the structures of leishmania mexicana cofactor-independent phosphoglycerate mutase (lm ipgam) crystallised with the substrate 3-phosphoglycerate at high and low cobalt concentrations have been solved at 2.00- and 1.90-a resolutions. both structures are very similar and the active site contains both 3-phosphoglycerate and 2-phosphoglycerate at equal occupancies (50%). lm ipgam co-crystallised with the product 2-phosphoglycerate yields the same structure. two co(2+) are coordinated within the acti ...200919781556
epr and endor characterization of the reactive intermediates in the generation of no by cryoreduced oxy-nitric oxide synthase from geobacillus stearothermophilus.cryoreduction epr/endor/step-annealing measurements with substrate complexes of oxy-gsnos (3; gsnos is nitric oxide synthase from geobacillus stearothermophilus) confirm that compound i (6) is the reactive heme species that carries out the gsnos-catalyzed (stage i) oxidation of l-arginine to n-hydroxy-l-arginine (noha), whereas the active species in the (stage ii) oxidation of noha to citrulline and hno/no(-) is the hydroperoxy-ferric form (5). when 3 is reduced by tetrahydrobiopterin (bh4), ins ...200919754116
safety evaluation of highly-branched cyclic dextrin and a 1,4-alpha-glucan branching enzyme from bacillus stearothermophilus.highly-branched cyclic dextrin (hbcd), a dextrin food ingredient presently only used in japan, was investigated for digestibility and potential toxicity. hbcd was readily hydrolyzed in vitro to maltose and maltotriose by human salivary and porcine pancreatic alpha-amylases. incubation of hbcd with a rat intestinal homogenate, containing digestive enzymes, resulted in the formation of maltose, maltotriose, and maltotetraose, and with longer incubation times, resulted in the formation of glucose. ...200919651182
evolved beta-galactosidases from geobacillus stearothermophilus with improved transgalactosylation yield for galacto-oligosaccharide production.a mutagenesis approach was applied to the beta-galactosidase bgab from geobacillus stearothermophilus kve39 in order to improve its enzymatic transglycosylation of lactose into oligosaccharides. a simple screening strategy, which was based on the reduction of the hydrolysis of a potential transglycosylation product (lactosucrose), provided mutant enzymes possessing improved synthetic properties for the autocondensation product from nitrophenyl-galactoside and galacto-oligosaccharides (gos) from ...200919666723
structure of the apo decarbamylated form of 2,3-diketo-5-methylthiopentyl-1-phosphate enolase from bacillus subtilis.2,3-diketo-5-methylthiopentyl-1-phosphate enolase (dk-mtp-1p enolase), a rubisco-like protein (rlp), catalyzes the enolization of 2,3-diketo-5-methylthiopentyl-1-phosphate. the crystal structure of the apo decarbamylated form (e form) of bacillus subtilis dk-mtp-1p enolase (bs-dk-mtp-1p enolase) has been determined at 2.3 a resolution. the overall structure of the e form of bs-dk-mtp-1p enolase highly resembles that of geobacillus kaustophilus dk-mtp-1p enolase (gk-dk-mtp-1p enolase), with the e ...200919690372
metabolic engineering of geobacillus thermoglucosidasius for high yield ethanol production.we describe the metabolic engineering of two strains of geobacillus thermoglucosidasius to divert their fermentative carbon flux from a mixed acid pathway, to one in which ethanol becomes the major product. this involved elimination of the lactate dehydrogenase and pyruvate formate lyase pathways by disruption of the ldh and pflb genes, respectively, together with upregulation of expression of pyruvate dehydrogenase. unlike the situation in escherichia coli, pyruvate dehydrogenase is active unde ...200919703579
evaluation of the efficacy of a low temperature steam and formaldehyde steriliser by using biological indicators. 200919703722
molecular characterization of the alkb gene in the thermophilic geobacillus sp. strain mh-1.an extremely thermophilic alkane-degrading bacterium, strain mh-1, was isolated from the deep subterranean petroleum reservoir in shengli oil field, pr china. based on its physiological characteristics and analysis of its 16s rrna gene sequence, strain mh-1 was identified as geobacillus stearothermophilus. strain mh-1 was able to grow at temperatures ranging from 50 to 72 degrees c and effectively degraded hexadecane as the sole carbon source at 70 degrees c. strain mh-1 degraded alkanes with di ...200919733653
molecular interplay between the replicative helicase dnac and its loader protein dnai from geobacillus kaustophilus.helicase loading factors are thought to transfer the hexameric ring-shaped helicases onto the replication fork during dna replication. however, the mechanism of helicase transfer onto dna remains unclear. in bacillus subtilis, the protein dnai, which belongs to the aaa+ family of atpases, is responsible for delivering the hexameric helicase dnac onto dna. here we investigated the interaction between dnac and dnai from geobacillus kaustophilus hta426 (gkdnac and gkdnai, respectively) and determin ...200919744498
interaction of human dna polymerase alpha and dna polymerase i from bacillus stearothermophilus with hypoxanthine and 8-oxoguanine nucleotides.to better understand how dna polymerases interact with mutagenic bases, we examined how human dna polymerase alpha (pol alpha), a b family enzyme, and dna polymerase from bacillus stearothermophilus (bf), an a family enzyme, generate adenine:hypoxanthine and adenine:8-oxo-7,8-dihydroguanine (8-oxog) base pairs. pol alpha strongly discriminated against polymerizing datp opposite 8-oxog, and removing n1, n(6), or n7 further inhibited incorporation, whereas removing n3 from datp dramatically increa ...200919642651
mg2+-assisted catalysis by b. stearothermophilus trprs is promoted by allosteric effects.mn(2+)-assisted catalysis by b. stearothermophilus trprs parallels that in polymerases and reduces specificity in amino acid activation. as predicted by nonequilibrium molecular dynamics simulations, multivariant thermodynamic cycles with [atp]-dependent michaelis-menten kinetics and mn(2+) for mg(2+) substitution demonstrate energetic coupling of atp affinities to the metal; to lysines k111 and k192, which interact via the ppi leaving group; and to k195, which couples differently to the metal v ...200919604475
toxicity assessment of the herbicide metolachlor comparative effects on bacterial and mitochondrial model systems.metolachlor is one of the most intensively used chloroacetamide herbicides. however, its effects on the environment and on non-target animals and humans as well as its interference at a cell/molecular level have not yet been fully elucidated. the aim of this study was: firstly, to evaluate the potential toxicity of metolachlor at a cell/subcellular level by using two in vitro biological model systems (a strain of bacillus stearothermophilus and rat liver mitochondria); secondly, to evaluate the ...200919607910
structural basis for thermostability revealed through the identification and characterization of a highly thermostable phosphotriesterase-like lactonase from geobacillus stearothermophilus.a new enzyme homologous to phosphotriesterase was identified from the bacterium geobacillus stearothermophilus (gsp). this enzyme belongs to the amidohydrolase family and possesses the ability to hydrolyze both lactone and organophosphate (op) compounds, making it a phosphotriesterase-like lactonase (pll). gsp possesses higher op-degrading activity than recently characterized plls, and it is extremely thermostable. gsp is active up to 100 degrees c with an energy of activation of 8.0 kcal/mol to ...200919615330
guidelines for interpretation of 16s rrna gene sequence-based results for identification of medically important aerobic gram-positive bacteria.this study is believed to be the first to provide guidelines for facilitating interpretation of results based on full and 527 bp 16s rrna gene sequencing and microseq databases used for identifying medically important aerobic gram-positive bacteria. overall, full and 527 bp 16s rrna gene sequencing can identify 24 and 40 % of medically important gram-positive cocci (gpc), and 21 and 34 % of medically important gram-positive rods (gpr) confidently to the species level, whereas the full-microseq a ...200919528178
identification of a novel two-peptide lantibiotic, lichenicidin, following rational genome mining for lanm proteins.lantibiotics are ribosomally synthesized peptide antimicrobials which contain considerable posttranslational modifications. given their usually broad host range and their highly stable structures, there have been renewed attempts to identify and characterize novel members of the lantibiotic family in recent years. the increasing availability of bacterial genome sequences means that in addition to traditional microbiological approaches, in silico screening strategies may now be employed to the sa ...200919561184
mcsb is a protein arginine kinase that phosphorylates and inhibits the heat-shock regulator ctsr.all living organisms face a variety of environmental stresses that cause the misfolding and aggregation of proteins. to eliminate damaged proteins, cells developed highly efficient stress response and protein quality control systems. we performed a biochemical and structural analysis of the bacterial ctsr/mcsb stress response. the crystal structure of the ctsr repressor, in complex with dna, pinpointed key residues important for high-affinity binding to the promoter regions of heat-shock genes. ...200919498169
cloning and characterization of flagellin genes and identification of flagellin glycosylation from thermophilic bacillus species.flagellin glycosylation was identified in bacillus sp. ps3 and geobacillus stearothermophilus. in vivo complementation showed that these flagellin genes did not restore the motility of a bacillus subtilis flagellin mutant, whereas the genes encoding non-glycosylated flagellin from geobacillus kaustophilus and bacillus sp. kps3 restored motility. moreover, four types of flagellins expressed in b. subtilis were not glycosylated. we speculate that glycosylation is required for flagellar filament as ...200919502747
crystal structure of an inverting gh 43 1,5-alpha-l-arabinanase from geobacillus stearothermophilus complexed with its substrate.arabinanases are glycosidases that hydrolyse alpha-(1-->5)- arabinofuranosidic linkages found in the backbone of the pectic polysaccharide arabinan. here we describe the biochemical characterization and the enzyme-substrate crystal structure of an inverting family 43 arabinanase from geobacillus stearothermophilus t-6 (abnb). based on viscosity and reducing power measurements, and based on product analysis for the hydrolysis of linear arabinan by abnb, the enzyme works in an endo mode of action. ...200919505290
interaction of if2 with the ribosomal gtpase-associated center during 70s initiation complex formation.addition of an escherichia coli 50s subunit (50s(cy5)) containing a cy5-labeled l11 n-terminal domain (l11-ntd) within the gtpase-associated center (gac) to an e. coli 30s initiation complex (30sic(cy3)) containing cy3-labeled initiation factor 2 complexed with gtp leads to rapid development of a fret signal during formation of the 70s initiation complex (70sic). initiation factor 2 (if2) and elongation factor g (ef-g) induce similar changes in ribosome structure. here we show that such similari ...200919366171
structural and mutational analyses of deinococcus radiodurans uvra2 provide insight into dna binding and damage recognition by uvras.uvra proteins are key actors in dna damage repair and play an essential role in prokaryotic nucleotide excision repair (ner), a pathway that is unique in its ability to remove a broad spectrum of dna lesions. understanding the dna binding and damage recognition activities of the uvra family is a critical component for establishing the molecular basis of this process. here we report the structure of the class ii uvra2 from deinococcus radiodurans in two crystal forms. these structures, coupled wi ...200919368888
[transglycosylation of benzo[h]quinazolines].this was the first study to apply cyclodextrin glucanotransferases (cgtase, ec 2.4.1.19) produced by mesophilic, thermophilic, alkaliphilic, and halophilic bacilli as well as pullulanase, beta-amylase, beta-galactosidase, and beta-fructofuranosidase for transglycosylation of benzo[h]quinazolines. the combination of cgtase produced by bacillus stearothermophilus st-88 and gamma-cyclodextrin (cd) used as a donor of glucosyl residues was the most efficient. the derivatives obtained are water-solubl ...200919382700
the high-molecular-mass amylase (hmma) of geobacillus stearothermophilus atcc 12980 interacts with the cell wall components by virtue of three specific binding regions.the complete nucleotide sequence encoding the high-molecular-mass amylase (hmma) of geobacillus stearothermophilus atcc 12980 was established by pcr techniques. based on the hmma gene sequence, the full-length rhmma, four n- or c-terminal rhmma truncations as well as three c-terminal rhmma fragments were cloned and heterologously expressed in escherichia coli. purified rhmma forms were used either for affinity studies with the recombinant (r) s-layer protein sbsc (rsbsc), peptidoglycan-containin ...200919460092
structure of the sporulation histidine kinase inhibitor sda from bacillus subtilis and insights into its solution state.the crystal structure of the dna-damage checkpoint inhibitor of sporulation, sda, from bacillus subtilis, has been solved by the mad technique using selenomethionine-substituted protein. the structure closely resembles that previously solved by nmr, as well as the structure of a homologue from geobacillus stearothermophilus solved in complex with the histidine kinase kinb. the structure contains three molecules in the asymmetric unit. the unusual trimeric arrangement, which lacks simple internal ...200919465772
cold plasma technology: bactericidal effects on geobacillus stearothermophilus and bacillus cereus microorganisms.cold plasma, also known as low temperature atmospheric pressure plasma (ltapp) is a novel technology consisting of neutral and charged particles, including free radicals, which can be used to destroy or inactivate microorganisms. research has been conducted regarding the effect of cold plasma on gram-positive bacteria; however, there is limited research regarding its ability to inactivate the spore-formers geobacillus stearothermophilus and bacillus cereus.200919470230
safety evaluation of 1,4-alpha-glucan branching enzymes from bacillus stearothermophilus and aquifex aeolicus expressed in bacillus subtilis.1,4-alpha-glucan branching enzyme (be; ec 2.4.1.18) is a key biocatalyst in the synthesis of polysaccharides, and is therefore useful in the production of food ingredients. the bes evaluated in this study (be-01 and be-02) are obtained by fermentation of bacillus subtilis expressing the be gene from either bacillus stearothermophilus strain trbe14 or aquifex aeolicus strain vf5. the safety of be-01 and be-02 have not been previously evaluated, and therefore, both were subjected to standard toxic ...200919470400
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