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phosphorylation of spore coat proteins by a family of atypical protein kinases.the modification of proteins by phosphorylation occurs in all life forms and is catalyzed by a large superfamily of enzymes known as protein kinases. we recently discovered a family of secretory pathway kinases that phosphorylate extracellular proteins. one member, family with sequence similarity 20c (fam20c), is the physiological golgi casein kinase. while examining distantly related protein sequences, we observed low levels of identity between the spore coat protein h (coth), and the fam20c-re ...201627185916
synthesis and characterization of zno:ceo2:nanocellulose:pani bionanocomposite. a bimodal agent for arsenic adsorption and antibacterial action.in the present study we report the generation of a bimodal, zno:ceo2:nanocellulose:polyaniline bionanocomposite having an appreciable remediation efficiency for dissolved arsenic along with a noticeable antibacterial activity. the microstructural analysis of the synthesized bionanocomposite was carried out by tem, xrd and ftir studies, which confirmed the incorporation of the nanoscaled zno and ceo2 in the polymeric nanocellulose:polyaniline matrix. the bionanocomposite exhibited a remediation e ...201627185154
xylitol production from waste xylose mother liquor containing miscellaneous sugars and inhibitors: one-pot biotransformation by candida tropicalis and recombinant bacillus subtilis.the process of industrial xylitol production is a massive source of organic pollutants, such as waste xylose mother liquor (wxml), a viscous reddish-brown liquid. currently, wxml is difficult to reuse due to its miscellaneous low-cost sugars, high content of inhibitors and complex composition. wxml, as an organic pollutant of hemicellulosic hydrolysates, accumulates and has become an issue of industrial concern in china. previous studies have focused only on the catalysis of xylose in the hydrol ...201627184671
complete genome sequence of bacillus subtilis bsd-2, a microbial germicide isolated from cultivated cotton.bacillus subtilis bsd-2, isolated from cotton (gossypium spp.), had strong antagonistic activity to verticillium dahlia kleb and botrytis cinerea. we sequenced and annotated the bsd-2 complete genome to help us the better use of this strain, which has surfactin, bacilysin, bacillibactin, subtilosin a, tas a and a potential class iv lanthipeptide biosynthetic pathways.201627184432
improving productive performance and mitigating harmful emissions from laying hen excreta via feeding on graded levels of corn ddgs with or without bacillus subtilis probiotic.an experiment that included some inclusions of corn distillers dried grains with solubles (ddgs) with or without supplementation of probiotic bacteria to hi-sex brown laying hen diets was conducted to evaluate the impacts on performance, egg quality, blood metabolites and nitrogen and phosphorus excretion in the manure. a total of 216 twenty-two-week-old hi-sex brown laying hens were randomly divided into eight treatment groups in a factorial design (4 × 2) experiment, which included four levels ...201627184423
optimization of extracellular polymeric substances production using azotobacter beijreinckii and bacillus subtilis and its application in chromium (vi) removal.extracellular polymeric substances (eps) of microbial origin are complex biopolymers and vary greatly in their chemical composition. they have a great potential in chelation of metal ions. in this work, the effect of growth phase, temperature and ph on production of eps by two bacteria azotobacter beijreinckii and bacillus subtilis have been studied. extracted eps was used to remove cr(vi) from aqueous system. a. beijreinckii produced maximum eps after 24h at ph 7 and temperature 30°c while b. s ...201627183236
development of a mediated whole cell-based electrochemical biosensor for joint toxicity assessment of multi-pollutants using a mixed microbial consortium.since most risk assessment for toxicants is based on individual single-species test, the deduction of such results to ecosystem evaluation is afflicted with uncertainties. herein, we successfully developed a p-benzoquinone mediated whole-cell electrochemical biosensor for multi-pollutants toxicological analysis by co-immobilizing mixed strains of microorganism, including escherichia coli (gram-negative bacteria), bacillus subtilis (gram-positive bacteria) and saccharomyces cerevisiae (fungus). t ...201627181640
formation of guaiacol by spoilage bacteria from vanillic acid, a product of rice koji cultivation, in japanese sake brewing.the formation of guaiacol, a potent phenolic off-odor compound in the japanese sake brewing process, was investigated. eight rice koji samples were analyzed, and one contained guaiacol and 4-vinylguaiacol (4-vg) at extraordinarily high levels: 374 and 2433 μg/kg dry mass koji, respectively. all samples contained ferulic and vanillic acids at concentrations of mg/kg dry mass koji. guaiacol forming microorganisms were isolated from four rice koji samples. they were identified as bacillus subtilis, ...201627181257
eco-friendly drugs from the marine environment: spongeweed-synthesized silver nanoparticles are highly effective on plasmodium falciparum and its vector anopheles stephensi, with little non-target effects on predatory copepods.mosquitoes act as vectors of devastating pathogens and parasites, representing a key threat for millions of humans and animals worldwide. the control of mosquito-borne diseases is facing a number of crucial challenges, including the emergence of artemisinin and chloroquine resistance in plasmodium parasites, as well as the presence of mosquito vectors resistant to synthetic and microbial pesticides. therefore, eco-friendly tools are urgently required. here, a synergic approach relying to nanotec ...201627180838
a non-invasive method for studying viral dna delivery to bacteria reveals key requirements for phage spp1 dna entry in bacillus subtilis cells.bacteriophages use most frequently a tail apparatus to create a channel across the entire bacterial cell envelope to transfer the viral genome to the host cell cytoplasm, initiating infection. characterization of this critical step remains a major challenge due to the difficulty to monitor dna entry in the bacterium and its requirements. in this work we developed a new method to study phage dna entry that has the potential to be extended to many tailed phages. its application to study genome del ...201627179995
visualizing ensembles in structural biology.displaying a single representative conformation of a biopolymer rather than an ensemble of states mistakenly conveys a static nature rather than the actual dynamic personality of biopolymers. however, there are few apparent options due to the fixed nature of print media. here we suggest a standardized methodology for visually indicating the distribution width, standard deviation and uncertainty of ensembles of states with little loss of the visual simplicity of displaying a single representative ...201627179343
heavy metals species affect fungal-bacterial synergism during the bioremediation of fluoranthene.the co-occurrence of polycyclic aromatic hydrocarbons (pahs) with heavy metals (hms) is very common in contaminated soils, but the influence of hms on fungal-bacterial synergism during pah bioremediation has not been investigated. the bioremediation of fluoranthene-contaminated sand using co-cultures of acremonium sp. p0997 and bacillus subtilis showed increases of 109.4 and 9.8 % in degradation compared to pure bacterial and fungal cultures, respectively, removing 64.1 ± 1.4 % fluoanthene in to ...201627178182
mechanically stiff, zinc cross-linked nanocomposite scaffolds with improved osteostimulation and antibacterial properties.nanocomposite scaffolds are studied widely due to their resemblance with the natural extracellular matrix of bone; but their use as a bone tissue engineered scaffold is clinically hampered due to low mechanical stiffness, inadequate osteoconduction, and graft associated infections. the purpose of the current study was the development of a mechanically stiff nanocomposite scaffold using biodegradable gellan and xanthan polymers reinforced with bioglass nanoparticles (nb) (size: 20-120 nm). these ...201627176647
subtilisin qk-2: secretory expression in lactococcus lactis and surface display onto gram-positive enhancer matrix (gem) particles.purified from the supernatant of bacillus subtilis qk02 culture broth, subtilisin qk-2 is a type of effective thrombolytic reagent that has great exploitable potential. however, the unbearable flavor that occurs with fermentation and the complicated methods that are required to obtain pure products limit the application of this enzyme. lactic acid bacteria (lab)-based delivery vehicles are promising as cheap and safe options for medicinal compounds. the secretory expression and surface display u ...201627176475
structural analysis and insights into the oligomeric state of an arginine-dependent transcriptional regulator from bacillus halodurans.the arginine repressor (argr) is an arginine-dependent transcription factor that regulates the expression of genes encoding proteins involved in the arginine biosynthesis and catabolic pathways. argr is a functional homolog of the arginine-dependent repressor/activator ahrc from bacillus subtilis, and belongs to the argr/ahrc family of transcriptional regulators. in this research, we determined the structure of the argr (bh2777) from bacillus halodurans at 2.41 å resolution by x-ray crystallogra ...201627171430
[study of the accumulation of rec a from bacillus subtilis in the mitochondria of a recombinant strain of the yeast yarrowia lipolytica].no eukaryotic species has a system for homologous dna recombination of the mitochondrial genome. we report on an integrative genetic systembased on the pq-srus construct that allows the expression of the reca recombinase from bacillus subtilis and its transportation to mitochondria of yarrowia lipolytica. the targeting of recombinant reca to mitochondria is provided by leader sequences (5'-utr and 3-utr) derived from the sod2 gene mrna, which exhibit affinity to the outer mitochondrial membrane ...201627266246
construction of probe of the plant growth-promoting bacteria bacillus subtilis useful for fluorescence in situ hybridization. 201627263830
growth inhibition of s. cerevisiae, b. subtilis, and e. coli by lignocellulosic and fermentation products.this paper describes the effect of several inhibiting components on three potential hosts for the bio-based production of methyl propionate, namely, wild-type escherichia coli and bacillus subtilis, and evolved saccharomyces cerevisiae ims0351. the inhibition by the lignocellulose-derived products 5-hydroxymethyl-2-furaldehyde, vanillin, and syringaldehyde and the fermentation products 2-butanol, 2-butanone, methyl propionate, and ethyl acetate has been assessed for these strains in defined medi ...201627262569
thrr, a dna-binding transcription factor involved in controlling threonine biosynthesis in bacillus subtilis.the threonine dehydratase ilva is part of the isoleucine biosynthesis pathway in the gram-positive model bacterium bacillus subtilis. consequently, deletion of ilva causes isoleucine auxotrophy. it has been reported that ilva pseudo-revertants having a derepressed hom-thrcb operon appear in the presence of threonine. here we have characterized two classes of ilva pseudo-revertants. in the first class the hom-thrcb operon was derepressed unmasking the threonine dehydratase activity of the threoni ...201627260660
development of a crispr-cas9 tool kit for comprehensive engineering of bacillus subtilis.the establishment of a clustered regularly interspaced short palindromic repeat (crispr)-cas9 system for strain construction in bacillus subtilis is essential for its progression toward industrial utility. here we outline the development of a crispr-cas9 tool kit for comprehensive genetic engineering in b. subtilis in addition to site-specific mutation and gene insertion, our approach enables continuous genome editing and multiplexing and is extended to crispr interference (crispri) for transcri ...201627260361
subunit arrangement in gpsb, a regulator of cell wall biosynthesis.gpsb, a key regulator of cell division in gram-positive bacteria, interacts with a key peptidoglycan synthase at the cell division septum, the penicillin binding protein pbp1 (a.k.a. pona). bacillus subtilis gpsb has been reported to interact with other components of the cell division machinery, including ezra, mrec, and prkc. in this study, we report an analysis of the arrangement of subunits in listeria monocytogenes gpsb by small-angle x-ray scattering. the resulting model has an elongated sh ...201627257764
draft genome sequence of bacillus subtilis alba01, a strain with antagonistic activity against the soilborne fungal pathogen of onion setophoma terrestris.bacillus subtilis is a nonpathogenic bacterium that lives in soil and has long been used as biological control agent in agriculture. here, we report the genome sequence of a b. subtilis strain isolated from rhizosphere of onion that shows strong biological activity against the soilborne fungal pathogen setophoma terrestris.201627257193
design of a crispr-cas system to increase resistance of bacillus subtilis to bacteriophage spp1.clustered regularly interspaced short palindromic repeats (crispr) together with crispr-associated (cas) genes form an adaptive prokaryotic immune system which provides acquired resistance against viruses and plasmids. bacillus subtilis presently is the best-characterized laboratory model for gram-positive bacteria and also widely used for industrial production of enzymes, vitamins and antibiotics. in this study, we show that type ii-a crispr-cas system from streptococcus thermophilus can be tra ...201627255973
second messenger signaling in bacillus subtilis: accumulation of cyclic di-amp inhibits biofilm formation.the gram-positive model organism bacillus subtilis produces the essential second messenger signaling nucleotide cyclic di-amp. in b. subtilis and other bacteria, c-di-amp has been implicated in diverse functions such as control of metabolism, cell division and cell wall synthesis, and potassium transport. to enhance our understanding of the multiple functions of this second messenger, we have studied the consequences of c-di-amp accumulation at a global level by a transcriptome analysis. c-di-am ...201627252699
botanical and biological pesticides elicit a similar induced systemic response in tomato (solanum lycopersicum) secondary metabolism.natural pesticides have attracted substantial interest due to the increase in organic agriculture and enhanced attention to environmental pollution. plant growth promoting bacteria (pgpb) are applied for both disease control and growth enhancement; pgpbs are known to elicit induced systemic response (isr) in plants. however, less is known about the effect of botanical pesticides, such as the azadirachtin-containing neem extracts, on plant metabolism. this study aimed to investigate the effects o ...201627251587
a rich morphological diversity of biosaline drying patterns is generated by different bacterial species, different salts and concentrations: astrobiological implications.biosaline formations (bsfs) are complex self-organized biomineral patterns formed by "hibernating" bacteria as the biofilm that contains them dries out. they were initially described in drying biofilms of escherichia coli cells + nacl. due to their intricate 3-d morphology and anhydrobiosis, these biomineralogical structures are of great interest in astrobiology. here we report experimental data obtained with various alkali halide salts (naf, nacl, nabr, licl, kcl, cscl) on bsf formation with e. ...201627248296
fermentation of purple jerusalem artichoke extract to improve the α-glucosidase inhibitory effect in vitro and ameliorate blood glucose in db/db mice.jerusalem artichoke has inhibitory activity against α-glucosidase and decreases fasting serum glucose levels, which may be related to its fructan content. the biological activity of fructan can be influenced by the degree of polymerization. thus, in this study, the inhibitory effects of original and fermented purple jerusalem artichoke (pja) on α-glucosidase were compared in vitro. additionally, the anti-diabetes effect of lactobacillus plantarum-fermented pja (lja) was studied in a non-insulin- ...201627247724
assessment of antioxidant, anticancer and antimicrobial activity of two vegetable species of amaranthus in bangladesh.amaranthus (amaranthaceae) has previously been reported to possess different bioactive phytochemicals including phenols, tannins and flavonoids. the current study was designed to evaluate the antioxidant, anti-proliferative and antimicrobial activity of stem and seed extracts of amaranthus lividus (al) and amaranthus hybridus (ah), respectively.201627246877
anti-tyrosinase kinetics and antibacterial process of caffeic acid n-nonyl ester in chinese olive (canarium album) postharvest.enzymatic browning and bacterial putrefaction are mainly responsible for quality losses of chinese olive (canarium album) postharvest and lead to very short shelf life on average. screening anti-browning and anti-bacterial agents is important for preservation of chinese olive. caffeic acid n-nonyl ester (c-9) and caffeic acid n- heptyl ester (c-7) was synthesized as inhibitors of tyrosinase, which is a key enzyme in browning process. the compound of c-9 could inhibit the activity of tyrosinase s ...201627246378
protein-primed replication of bacteriophage φ29 dna.the requirement of dna polymerases for a 3'-hydroxyl (3'-oh) group to prime dna synthesis raised the question about how the ends of linear chromosomes could be replicated. among the strategies that have evolved to handle the end replication problem, a group of linear phages and eukaryotic and archaeal viruses, among others, make use of a protein (terminal protein, tp) that primes dna synthesis from the end of their genomes. the replicative dna polymerase recognizes the oh group of a specific res ...201627241929
overexpression and secretion of agaa7 from pseudoalteromonas hodoensis sp. nov in bacillus subtilis for the depolymerization of agarose.interest in agar or agarose-based pharmaceutical products has driven the search for potent agarolytic enzymes. an extracellular β-agarase (agaa7) recently isolated from pseudoalteromonas hodoensis sp. nov was expressed in bacillus subtilis, which was chosen due to its capability to overproduce and secrete functional enzymes. phenotypic analysis showed that the engineered b. subtilis secreted a functional agaa7 when fused with the apre signal peptide (sp) at the amino-terminus. the maximum agarol ...201627241288
mutational probing of protein aggregates to design aggregation-resistant proteins.characterization of amorphous protein aggregates may offer insights into the process of aggregation. eleven single amino acid mutants of lipase (lipa of bacillus subtilis) were subjected to temperature-induced aggregation, and the resultant aggregates were characterized for recovery of activity in the presence of guanidinium chloride (gdmcl). based on activity recovery profiles of the aggregates, the mutants could be broadly assigned into four groups. by including at least one mutation from each ...201627239434
optimization of hyaluronidase inhibition activity from prunus davidiana (carriere) franch fruit extract fermented by its isolated bacillus subtilis strain spf4211.strain spf4211, having hyaluronidase (haase) inhibition activity, was isolated from p. davidiana (carriere) franch fruit (prdf) sugar extract. the phenotypic and biochemical properties based on 16s rdna sequencing and an api 50 chb kit suggested that the organism was b. subtilis. to optimize the haase inhibition activity of prdf extract by fermentation of strain spf4211, a central composite design (ccd) was introduced based on three variables: concentration of prdf extract (x₁: 1-5%), amount of ...201627238939
anti-biofilm and sporicidal activity of peptides based on wheat puroindoline and barley hordoindoline proteins.the broad-spectrum activity of antimicrobial peptides (amps) and low probability of development of host resistance make them excellent candidates as novel bio-control agents. a number of amps are found to be cationic, and a small proportion of these are tryptophan-rich. the puroindolines (pin) are small, basic proteins found in wheat grains with proposed roles in biotic defence of seeds and seedlings. synthetic peptides based on their unique tryptophan-rich domain (trd) display antimicrobial pro ...201627238815
a comprehensive, crispr-based functional analysis of essential genes in bacteria.essential gene functions underpin the core reactions required for cell viability, but their contributions and relationships are poorly studied in vivo. using crispr interference, we created knockdowns of every essential gene in bacillus subtilis and probed their phenotypes. our high-confidence essential gene network, established using chemical genomics, showed extensive interconnections among distantly related processes and identified modes of action for uncharacterized antibiotics. importantly, ...201627238023
evolution: bacterial territoriality as a byproduct of kin discriminatory warfare.recent work suggests that the inability of genetically distinct colonies of the bacterium bacillus subtilis to freely merge is often a byproduct of microbial warfare mediated by divergent suites of chemical weaponry. any effects of such kin-discriminatory antagonisms on levels of within-group cooperation at other traits remain unclear.201627166695
hydraphiles enhance antimicrobial potency against escherichia coli, pseudomonas aeruginosa, and bacillus subtilis.hydraphiles are synthetic amphiphiles that form ion-conducting pores in liposomal membranes. these pores exhibit open-close behavior when studied by planar bilayer conductance techniques. in previous work, we showed that when co-administered with various antibiotics to the dh5α strain of escherichia coli, they enhanced the drug's potency. we report here potency enhancements at low concentrations of hydraphiles for the structurally and mechanistically unrelated antibiotics erythromycin, kanamycin ...201627166575
studies on bioactivity and secondary metabolites of crude extracts of bidens pilosa l. (asteraceae): a medicinal plant used in the transkei region of south africa.whole plant-parts of bidens pilosa were powdered and extracted in concentrated hexane, acetone, ethanol, methanol and water. the extracts were tested for antimicrobial activity against escherichia coli (25922), bacillus subtilis (atcc 6051), enterococcus faecalis (51299) staphylococcus aureus (atcc 29213) and pseudomonas aeruginosa (atcc127853), using standard microbiological techniques. active crude extracts were macerated in concentrated methanol and tested for secondary metabolites including ...201627166532
crystal structure of bacillus subtilis cysteine desulfurase sufs and its dynamic interaction with frataxin and scaffold protein sufu.the biosynthesis of iron sulfur (fe-s) clusters in bacillus subtilis is mediated by a suf-type gene cluster, consisting of the cysteine desulfurase sufs, the scaffold protein sufu, and the putative chaperone complex sufb/sufc/sufd. here, we present the high-resolution crystal structure of the sufs homodimer in its product-bound state (i.e., in complex with pyrodoxal-5'-phosphate, alanine, cys361-persulfide). by performing hydrogen/deuterium exchange (h/dx) experiments, we characterized the inter ...201627382962
discovery of new cellulases from the metagenome by a metagenomics-guided strategy.energy shortage has become a global problem. production of biofuels from renewable biomass resources is an inevitable trend of sustainable development. cellulose is the most abundant and renewable resource in nature. lack of new cellulases with unique properties has become the bottleneck of the efficient utilization of cellulose. environmental metagenomes are regarded as huge reservoirs for a variety of cellulases. however, new cellulases cannot be obtained easily by functional screening of meta ...201627382415
reconstitution and minimization of a micrococcin biosynthetic pathway in bacillus subtilis.thiopeptides represent one of several families of highly modified peptide antibiotics that hold great promise for natural product engineering. these macrocyclic peptides are produced by a combination of ribosomal synthesis and extensive posttranslational modification by dedicated processing enzymes. we previously identified a compact, plasmid-borne gene cluster for the biosynthesis of micrococcin p1 (mp1), an archetypal thiopeptide antibiotic. in an effort to genetically dissect this pathway, we ...201627381911
biology of icebs1, an integrative and conjugative element in bacillus subtilis.horizontal gene transfer plays a profound role in bacterial evolution by propelling the rapid transfer of genes and gene cassettes. integrative and conjugative elements (ices) are one important mechanism driving horizontal gene transfer. ices, also known as conjugative transposons, reside on the host chromosome but can excise to form a conjugative dna circle that is capable of transfer to other cells. analysis of the large number of completed bacterial genome sequences has revealed many previous ...201627381852
germ is required to assemble the basal platform of the spoiiia-spoiiq transenvelope complex during sporulation in bacillus subtilis.sporulating bacillus subtilis cells assemble a multimeric membrane complex connecting the mother cell and developing spore that is required to maintain forespore differentiation. an early step in the assembly of this transenvelope complex (called the a-q complex) is an interaction between the extracellular domains of the forespore membrane protein spoiiq and the mother cell membrane protein spoiiiah. this interaction provides a platform onto which the remaining components of the complex assemble ...201627381174
efficient secretion of the β-galactosidase bgal1-3 via both tat-dependent and tat-independent pathways in bacillus subtilis.in this study, the twin-arginine (tat) signal peptide phod was used to direct the secretion of the β-galactosidase bgal1-3 into the growth medium of an engineered strain of bacillus subtilis 168. after 24 h of cultivation, the extracellular activity reached 1.15 u/ml, representing 78% of the total activity. bgal1-3 was exported via both tat-dependent and tat-independent pathways. to improve the secretion amounts, two more copies of the target gene were inserted into the designated loci on the ch ...201627380825
promoter screening from bacillus subtilis in various conditions hunting for synthetic biology and industrial applications.the use of bacillus subtilis in synthetic biology and metabolic engineering is highly desirable to take advantage of the unique metabolic pathways present in this organism. to do this, an evaluation of b. subtilis' intrinsic biological parts is required to determine the best strategies to accurately regulate metabolic circuits and expression of target proteins. the strengths of promoter candidates were evaluated by measuring relative fluorescence units of a green fluorescent protein reporter, in ...201627380260
improvement of poly-γ-glutamic acid biosynthesis in a moving bed biofilm reactor by bacillus subtilis nx-2.the production of poly-γ-glutamic acid (γ-pga) by bacillus subtilis nx-2 using a moving bed biofilm reactor (mbbr) system was tested for the first time in this study. polypropylene tl-2 was chosen as a suitable carrier, and γ-pga concentration of 42.7±0.86g/l and productivity of 0.59±0.06g/(lh) were obtained in batch fermentation. after application of the strategy of dissolved oxygen (do)-stat feeding, higher γ-pga concentration and productivity were achieved than with glucose feedback feeding. ...201627376835
synthesis and antimicrobial activity of 1,2-benzothiazine derivatives.a number of 1,2-benzothiazines have been synthesized in a three-step process. nine chalcones 1-9 bearing methyl, fluoro, chloro and bromo substituents were chlorosulfonated with chlorosulfonic acid to generate the chalcone sulfonyl chlorides 10-18. these were converted to the dibromo compounds 19-27 through reaction with bromine in glacial acetic acid. compounds 19-27 were reacted with ammonia, methylamine, ethylamine, aniline and benzylamine to generate a library of 45 1,2-benzothiazines 28-72. ...201627376253
temporal regulation of the bacillus subtilis acetylome and evidence for a role of mreb acetylation in cell wall growth.n(ε)-lysine acetylation has been recognized as a ubiquitous regulatory posttranslational modification that influences a variety of important biological processes in eukaryotic cells. recently, it has been realized that acetylation is also prevalent in bacteria. bacteria contain hundreds of acetylated proteins, with functions affecting diverse cellular pathways. still, little is known about the regulation or biological relevance of nearly all of these modifications. here we characterize the cellu ...201627376153
fitness trade-offs in competence differentiation of bacillus subtilis.in the stationary phase, bacillus subtilis differentiates stochastically and transiently into the state of competence for transformation (k-state). the latter is associated with growth arrest, and it is unclear how the ability to develop competence is stably maintained, despite its cost. to quantify the effect differentiation has on the competitive fitness of b. subtilis, we characterized the competition dynamics between strains with different probabilities of entering the k-state. the relative ...201627375604
bio-remediation of acephate-pb(ii) compound contaminants by bacillus subtilis fzul-33.removal of pb(2+) and biodegradation of organophosphorus have been both widely investigated respectively. however, bio-remediation of both pb(2+) and organophosphorus still remains largely unexplored. bacillus subtilis fzul-33, which was isolated from the sediment of a lake, possesses the capability for both biomineralization of pb(2+) and biodegradation of acephate. in the present study, both pb(2+) and acephate were simultaneously removed via biodegradation and biomineralization in aqueous sol ...201627372122
structural features and functional dependency on β-clamp define distinct subfamilies of bacterial mismatch repair endonuclease mutl.in early reactions of dna mismatch repair, muts recognizes mismatched bases and activates mutl endonuclease to incise the error-containing strand of the duplex. dna sliding clamp is responsible for directing the mutl-dependent nicking to the newly synthesized/error-containing strand. in bacillus subtilis mutl, the β-clamp-interacting motif (β motif) of the c-terminal domain (ctd) is essential for both in vitro direct interaction with β-clamp and in vivo repair activity. a large cluster of negati ...201627369079
hard-wired control of bacterial processes by chromosomal gene location.bacterial processes, such as stress responses and cell differentiation, are controlled at many different levels. while some factors, such as transcriptional regulation, are well appreciated, the importance of chromosomal gene location is often underestimated or even completely neglected. a combination of environmental parameters and the chromosomal location of a gene determine how many copies of its dna are present at a given time during the cell cycle. here, we review bacterial processes that r ...201627364121
super resolution fluorescence microscopy and tracking of bacterial flotillin (reggie) paralogs provide evidence for defined-sized protein microdomains within the bacterial membrane but absence of clusters containing detergent-resistant proteins.biological membranes have been proposed to contain microdomains of a specific lipid composition, in which distinct groups of proteins are clustered. flotillin-like proteins are conserved between pro-and eukaryotes, play an important function in several eukaryotic and bacterial cells, and define in vertebrates a type of so-called detergent-resistant microdomains. using sted microscopy, we show that two bacterial flotillins, floa and flot, form defined assemblies with an average diameter of 85 to ...201627362352
food-grade expression of d-psicose 3-epimerase with tandem repeat genes in bacillus subtilis.an integrative food-grade expression system with tandem repeat target genes was constructed for the expression of d-psicose 3-epimerase (dpease; ec 5.1.3.30). the dpease gene fused with the p43 promoter constituted an independent monomeric expression cassette. multimers of the expression cassette were constructed in vitro using the isocaudamer strategy. the recombinant integration plasmids pdg-ndpe (n = 1, 2, 3), which contained one, two, or three consecutive p43-dpease tandem repeats, were inte ...201627358033
antioxidant and antimicrobial capacities of ethanolic extract of pergularia daemia leaves: a possible substitute in diabetic management.the leaves of pergularia daemia forsk (family asclepidaceae) provide alternative plant-based treatments for the management of diabetes mellitus and diarrhoea in both humans and indigenous poultry species like the guinea fowls (numida meleagris). however, no scientific investigations to validate its usefulness in ghana have been established. this study therefore sought to investigate the anti-hyperglycaemic activity of the 70 % ethanolic extract of p. daemia using streptozotocin (stz)-induced dia ...201627352448
sol-gel synthesis of thorn-like zno nanoparticles endorsing mechanical stirring effect and their antimicrobial activities: potential role as nano-antibiotics.the effect of mechanical stirring on sol-gel synthesis of thorn-like zno nanoparticles (zno-nps) and antimicrobial activities is successfully reported in this study. the in-house synthesized nanoparticles were characterized by xrd, sem, tem, ftir, tga, dsc and uv-visible spectroscopy. the x-ray diffraction analysis revealed the wurtzite crystal lattice for zno-nps with no impurities present. the diametric measurements of the synthesized thorn-like zno-nps (morphology assessed by sem) were well a ...201627349836
[expression of pleurocidin from winter flounder in escherichia coli and optimization of culture conditions].to express pleurocidin in escherichia coli and to enhance the secretory efficiency of the fusion protein, the gene encoding pleurocidin was ligated with cherry dna sequence via blunt-end ligation. then this fusion gene was cloned into pet22b (+) vector and the recombinant plasmid was transformed into e. coli bl21 (de3). lactose was used to induce expression of fusion protein. the recombinant plasmid pet22b (+) -cp was successfully constructed and high-level expression of fusion protein was induc ...201627349119
activating and attenuating the amicoumacin antibiotics.the amicoumacins belong to a class of dihydroisocoumarin natural products and display antibacterial, antifungal, anticancer, and anti-inflammatory activities. amicoumacins are the pro-drug activation products of a bacterial nonribosomal peptide-polyketide hybrid biosynthetic pathway and have been isolated from gram-positive bacillus and nocardia species. here, we report the stimulation of a "cryptic" amicoumacin pathway in the entomopathogenic gram-negative bacterium xenorhabdus bovienii, a stra ...201627347911
narrow-spectrum inhibitors targeting an alternative menaquinone biosynthetic pathway of helicobacter pylori.we aimed to identify narrow-spectrum natural compounds that specifically inhibit an alternative menaquinone (mk; vitamin k2) biosynthetic pathway (the futalosine pathway) of helicobacter pylori. culture broth samples of 6183 microbes were examined using the paper disc method with different combinations of 2 of the following 3 indicator microorganisms: bacillus halodurans c-125 and kitasatospora setae km-6054(t), which have only the futalosine pathway of mk biosynthesis, and bacillus subtilis h17 ...201627346378
engineering corynebacterium glutamicum for fast production of l-lysine and l-pipecolic acid.the gram-positive corynebacterium glutamicum is widely used for fermentative production of amino acids. the world production of l-lysine has surpassed 2 million tons per year. glucose uptake and phosphorylation by c. glutamicum mainly occur by the phosphotransferase system (pts) and to lesser extent by inositol permeases and glucokinases. heterologous expression of the genes for the high-affinity glucose permease from streptomyces coelicolor and bacillus subtilis glucokinase fully compensated fo ...201627345060
fabrication of nano-mosquitocides using chitosan from crab shells: impact on non-target organisms in the aquatic environment.mosquitoes are arthropods of huge medical and veterinary relevance, since they vector pathogens and parasites of public health importance, including malaria, dengue and zika virus. currently, nanotechnology is considered a potential eco-friendly approach in mosquito control research. we proposed a novel method of biofabrication of silver nanoparticles (agnp) using chitosan (ch) from crab shells. ch-agnp nanocomposite was characterized by uv-vis spectroscopy, ftir, sem, edx and xrd. ch-agnp were ...201627344400
an expeditious four-component domino protocol for the synthesis of novel thiazolo[3,2-a]thiochromeno[4,3-d]pyrimidine derivatives as antibacterial and antibiofilm agents.an efficient domino protocol has been developed for the synthesis of new pyrimidine scaffolds, through a one-pot four-component cascade transformation via [bmim]hso4 ionic liquid mediated reaction, using an equimolar mixture of thiochroman-4-one, benzaldehyde, thiourea and 3-bromo-1-phenylpropan-1-one leading to the formation of a double electrophilic pyrimidine-2(5h)-thione intermediate. the intermediate regioselectively undergoes cyclization through intramolecular nh bond activation followed b ...201627344213
editing of the bacillus subtilis genome by the crispr-cas9 system.the clustered regularly interspaced short palindromic repeat (crispr)-associated (cas) systems are adaptive immune systems of bacteria. a type ii crispr-cas9 system from streptococcus pyogenes has recently been developed into a genome engineering tool for prokaryotes and eukaryotes. here, we present a single-plasmid system which allows efficient genome editing of bacillus subtilis the plasmid pjoe8999 is a shuttle vector that has a puc minimal origin of replication for escherichia coli, the temp ...201627342565
high-quality draft genome sequence of bacillus subtilis strain wausv36.bacillus subtilis strain wausv36 inhibits the growth of and decreases disease symptoms caused by the potato pathogen phytophthora infestans we determined the sequence of the 4.7-mbp genome of this strain. wausv36 shared very high nucleotide sequence identity with previously sequenced strains of b. subtilis.201627340068
dynamic organization of seca and secy secretion complexes in the b. subtilis membrane.in prokaryotes, about one third of cellular proteins are translocated across the plasma membrane or inserted into it by concerted action of the cytoplasmic atpase seca and the universally conserved secyeg heterotrimeric polypeptide-translocating pore. secretion complexes have been reported to localize in specific subcellular sites in bacillus subtilis. in this work, we used a combination of total internal reflection microscopy, scanning fluorescence correlation spectroscopy, and pair correlation ...201627336478
antibacterial activity of silver nanoparticles obtained by pulsed laser ablation in pure water and in chloride solution.silver nanoparticles (agnps) have increasingly gained importance as antibacterial agents with applications in several fields due to their strong, broad-range antimicrobial properties. agnp synthesis by pulsed laser ablation in liquid (plal) permits the preparation of stable ag colloids in pure solvents without capping or stabilizing agents, producing agnps more suitable for biomedical applications than those prepared with common, wet chemical preparation techniques. to date, only a few investiga ...201627335737
similarities and differences in combined toxicity of sulfonamides and other antibiotics towards bacteria for environmental risk assessment.antibiotics as a type of environmental contaminants are typically exposed to chemical mixtures over long periods of time, so chronic combined toxicity is the best way to perform an environmental risk assessment. in this paper, the individual and combined toxicity of sulfonamides (sas), sulfonamide potentiators (saps), and doxycycline hyclate (dh) were tested on gram-positive (bacillus subtilis, b. subtilis) and gram-negative (escherichia coli, e. coli) bacteria. the individual toxicity of antibi ...201627334345
purine biosynthesis is the bottleneck in trimethoprim-treated bacillus subtilis.trimethoprim is a folate biosynthesis inhibitor. tetrahydrofolates are essential for the transfer of c1 units in several biochemical pathways including purine, thymine, methionine, and glycine biosynthesis. this study addressed the effects of folate biosynthesis inhibition on bacterial physiology.201627329548
more than a hole: the holin lethal function may be required to fully sensitize bacteria to the lytic action of canonical endolysins.double-strand dna bacteriophages employ the holin-endolysin dyad as core components of different strategies to lyse bacterial hosts. in the so-called canonical model the holin holes play an essential role in lysis as they provide a conduit for passage of the cytoplasm-accumulated endolysin to the cell wall (cw), where it degrades the peptidoglycan. it is considered that once synthesized canonical endolysins immediately acquire their fully active conformation, having thus the capacity to efficien ...201627328857
a dynamic pathway analysis approach reveals a limiting futile cycle in n-acetylglucosamine overproducing bacillus subtilis.recent advances in genome engineering have further widened the gap between our ability to implement essentially any genetic change and understanding the impact of these changes on cellular function. we lack efficient methods to diagnose limiting steps in engineered pathways. here, we develop a generally applicable approach to reveal limiting steps within a synthetic pathway. it is based on monitoring metabolite dynamics and simplified kinetic modelling to differentiate between putative causes of ...201627324299
improving production of extracellular proteases by random mutagenesis and biochemical characterization of a serine protease in bacillus subtilis s1-4.the feather is a valuable by-product with a huge annual yield produced by the poultry industry. degradation of feathers by microorganisms is a prerequisite to utilize this insoluble protein resource. to improve the degrading efficiency of feathers, mutagenesis of the bacterium bacillus subtilis s1-4 was performed. by combining ultraviolet irradiation and n-methyl-n'-nitro-n-nitrosoguanidine treatment for mutagenesis, a high protease-producing mutant (umu4) of b. subtilis s1-4 was selected, which ...201627323184
ion trap mass spectrometry of surfactins produced by bacillus subtilis szmc 6179j reveals novel fragmentation features of cyclic lipopeptides.surfactins are mixtures of cyclic lipopeptides consisting of variants of a heptapeptide and a linked β-hydroxy fatty acid with various chain lengths of 13-15 carbon atoms. a lactone bridge between the β-hydroxy functional group of the fatty acid and the carboxy terminal functional component of the peptide chain form their cyclic structures. such lipopeptides, produced mainly by bacillus species, possess several remarkable biological effects such as antitumor and antimicrobial activities, some of ...201627321846
physical interaction and assembly of bacillus subtilis spore coat proteins cote and cotz studied by atomic force microscopy.the spore of bacillus subtilis, a dormant type of cell, is surrounded by a complex multilayered protein structure known as the coat. it is composed of over 70 proteins and essential for the spore to withstand extreme environmental conditions and allow germination under favorable conditions. however, understanding how the properties of the coat arise from the interactions among all these proteins is an important challenge. moreover, many specific protein-protein interactions among the coat protei ...201627320701
nitric oxide: a novel inducer for enhancement of microbial lipase production.the purpose of this study was to elucidate whether exogenous nitric oxide (no) has a potential beneficial effect on lipase production capacity of some microorganisms. sodium nitroprusside (snp) was used as an exogenous no donor in production medium. in comparison with the control (0 nm snp), snp concentrations from 10 to 100 nm induced lipase production in mesophilic bacterium bacillus subtilis and cold-adapted yeast yarrowia lipolytica. especially, the maximum lipase activities for y. lipolytic ...201627316859
identification and characterization of udp-glucose:phloretin 4'-o-glycosyltransferase from malus x domestica borkh.apples (malus x domestica brokh.) are among the world's most important food crops with nutritive and medicinal importance. many of the health beneficial properties of apple fruit are suggested to be due to (poly)phenolic metabolites, including various dihydrochalcones. although many of the genes and enzymes involved in polyphenol biosynthesis are known in many plant species, the specific reactions that lead to the biosynthesis of the sweet tasting dihydrochalcones, such as trilobatin, are unknow ...201627316677
programmable, pneumatically actuated microfluidic device with an integrated nanochannel array to track development of individual bacteria.we describe a microfluidic device with an integrated nanochannel array to trap individual bacteria and monitor growth and reproduction of lineages over multiple generations. our poly(dimethylsiloxane) device comprises a pneumatically actuated nanochannel array that includes 1280 channels with widths from 600 to 1000 nm to actively trap diverse bacteria. integrated pumps and valves perform on-chip fluid and cell manipulations that provide dynamic control of cell loading and nutrient flow, permitt ...201627314919
modeling and optimization of newfoundland shrimp waste hydrolysis for microbial growth using response surface methodology and artificial neural networks.the hydrolyzed protein derived from seafood waste is regarded as a premium and low-cost nitrogen source for microbial growth. in this study, optimization of enzymatic shrimp waste hydrolyzing process was investigated. the degree of hydrolysis (dh) with four processing variables including enzyme/substrate ratio (e/s), hydrolysis time, initial ph value and temperature, were monitored. the dh values were used for response surface methodology (rsm) optimization through central composite design (ccd) ...201627312986
catalytic mechanism of mray and weca, two paralogues of the polyprenyl-phosphate n-acetylhexosamine 1-phosphate transferase superfamily.the mray transferase catalyzes the first membrane step of bacterial cell wall peptidoglycan biosynthesis, namely the transfer of the n-acetylmuramoyl-pentapeptide moiety of the cytoplasmic precursor udp-murnac-pentapeptide to the membrane transporter undecaprenyl phosphate (c55p), yielding c55-pp-murnac-pentapeptide (lipid i). a paralogue of mray, weca, catalyzes the transfer of the phospho-glcnac moiety of udp-n-acetylglucosamine onto the same lipid carrier, leading to the formation of c55-pp-g ...201627312048
intermittent turbulence in flowing bacterial suspensions.dense suspensions of motile bacteria, possibly including the human gut microbiome, exhibit collective dynamics akin to those observed in classic, high reynolds number turbulence with important implications for chemical and biological transport, yet this analogy has remained primarily qualitative. here, we present experiments in which a dense suspension of bacillus subtilis bacteria was flowed through microchannels and the velocity statistics of the flowing suspension were quantified using a rece ...201627307513
multigene disruption in undomesticated bacillus subtilis atcc 6051a using the crispr/cas9 system.bacillus subtilis atcc 6051a is an undomesticated strain used in the industrial production of enzymes. because it is poorly transformable, genetic manipulation in this strain requires a highly efficient genome editing method. in this study, a streptococcus pyogenes crispr/cas9 system consisting of an all-in-one knockout plasmid containing a target-specific guide rna, cas9, and a homologous repair template was established for highly efficient gene disruption in b. subtilis atcc 6051a. with an eff ...201627305971
[effect of key-gene modification on uridine biosynthesis in bacillus subtilis].we studied several crucial factors influencing the uridine biosynthesis in bacillus subtilis, including mutations of phosphoribosylpyrophosphate synthetase (prpp synthetase) (prs) and carbamyl phosphate synthetase (pyraa/pyrab), and overexpression of heterologous 5'-nucleotidase (sdt1).201627305780
demonstration of carbon catabolite repression in naphthalene degrading soil bacteria via raman spectroscopy based stable isotope probing.carbon catabolite repression (ccr) is a regulatory phenomenon occurring in both lower organisms like bacteria and higher organisms like yeast, which allows them to preferentially utilize a specific carbon source to achieve highest metabolic activity and cell growth. ccr has been intensely studied in the model organisms escherichia coli and bacillus subtilis by following diauxic growth curves, assays to estimate the utilization or depletion of carbon sources, enzyme assays, western blotting and m ...201627305464
germination of spores of astrobiologically relevant bacillus species in high-salinity environments.in times of increasing space exploration and search for extraterrestrial life, new questions and challenges for planetary protection, aiming to avoid forward contamination of different planets or moons with terrestrial life, are emerging. spore-forming bacteria such as bacillus species have a high contamination potential due to their spores' extreme resistance, enabling them to withstand space conditions. spores require liquid water for their conversion into a growing cell (i.e., spore germinati ...201627304705
[an efficient method for genetic certification of bacillus subtilis strains, prospective producers of biopreparations].genetic certification of commercial strains of bacteria antagonistic to phytopathogenic microorganisms guarantees their unequivocal identification and confirmation of safety. in russia, unlike eu countries, genetic certification of bacillus subtilis strains is not used. based on the previously proposed double digestion selective label (ddsl) fingerprinting, a method for genetic identification and certification of b. subtilis strains was proposed. the method was tested on several strains differin ...201627301128
α-pyrones with diverse hydroxy substitutions from three marine-derived nocardiopsis strains.eight new α-pyrones 1-8 and three known α-pyrones 9-11 were isolated from three marine-derived nocardiopsis strains scsio 10419, scsio 04583, and scsio ks107. the structures of compounds 1-8 were elucidated by comprehensive spectral analyses. the absolute configurations of 4-deoxyphomapyrone c (1), 4-deoxy-11-hydroxyphomapyrone c (3), 4-deoxy-7r-hydroxyphomapyrone c (5), and phomapyrone c (11) were determined by tddft-ecd calculations for the solution conformers, which revealed that the conforma ...201627300427
just in case it rains: building a hydrophobic biofilm the bacillus subtilis way.over the millennia, diverse species of bacteria have evolved multiple independent mechanisms to structure sessile biofilm communities that confer protection and stability to the inhabitants. the gram-positive soil bacterium bacillus subtilis biofilm presents as an architecturally complex, highly hydrophobic community that resists wetting by water, solvents, and biocides. this remarkable property is conferred by a small secreted protein called bsla, which self-assembles into an organized lattice ...201627458867
f-type bacteriocins of listeria monocytogenes: a new class of phage tail-like structures reveals broad parallel coevolution between tailed bacteriophages and high-molecular-weight bacteriocins.listeria monocytogenes is a significant foodborne human pathogen that can cause severe disease in certain high-risk individuals. l. monocytogenes is known to produce high-molecular-weight, phage tail-like bacteriocins, or "monocins," upon induction of the sos system. in this work, we purified and characterized monocins and found them to be a new class of f-type bacteriocins. the l. monocytogenes monocin genetic locus was cloned and expressed in bacillus subtilis, producing specifically targeted ...201627457717
ozonation as an effective way to stabilize new kinds of fermentation media used in biotechnological production of liquid fuel additives.intermediates from processing sugar beets are considered an attractive feedstock for ethanol fermentation due to their high fermentable sugar content. in particular, medium prepared from raw sugar beet juice seems to be suitable for use in fermentation processes, but it is microbiologically unstable and requires sterilization.201627453725
toxin-antitoxin systems eliminate defective cells and preserve symmetry in bacillus subtilis biofilms.toxin-antitoxin modules are gene pairs encoding a toxin and its antitoxin, and are found on the chromosomes of many bacteria, including pathogens. here, we characterize the specific contribution of the txpa and yqcg toxins in elimination of defective cells from developing bacillus subtilis biofilms. on nutrient limitation, defective cells accumulated in the biofilm breaking its symmetry. deletion of the toxins resulted in accumulation of morphologically abnormal cells, and interfered with the pr ...201627450630
ag loaded wo3 nanoplates for efficient photocatalytic degradation of sulfanilamide and their bactericidal effect under visible light irradiation.sulfonamides (sas) are extensively used antibiotics and their residues in the water bodies propose potential threat to the public. in this study, degradation efficiency of sulfanilamide (sam), which is the precursor of sas, using wo3 nanoplates and their ag heterogeneous as photocatalysts was investigated. wo3 nanoplates with uniform size were synthesized by a facile one step hydrothermal method. different amount of ag nanoparticles (ag nps) were loaded onto wo3 nanoplates using a photo-reductio ...201627450332
an improvement of surfactin production by b. subtilis bbg131 using design of experiments in microbioreactors and continuous process in bubbleless membrane bioreactor.culture medium elements were analysed by a screening doe to identify their influence in surfactin specific production by a surfactin constitutive overproducing bacillus subtilis strain. statistics pointed the major enhancement caused by high glutamic acid concentrations, as well as a minor positive influence of tryptophan and glucose. successively, a central composite design was performed in microplate bioreactors using a biolector®, in which variations of these impressive parameters, glucose, g ...201627447921
germinants and their receptors in clostridia.many anaerobic spore-forming clostridial species are pathogenic, and some are industrially useful. although many are strict anaerobes, the bacteria persist under aerobic and growth-limiting conditions as multilayered metabolically dormant spores. for many pathogens, the spore form is what most commonly transmits the organism between hosts. after the spores are introduced into the host, certain proteins (germinant receptors) recognize specific signals (germinants), inducing spores to germinate an ...201627432831
enhancement of a high efficient autoinducible expression system in bacillus subtilis by promoter engineering.quorum-sensing related promoter srfa (psrfa) was used to construct autoinducible expression system for production of recombinant proteins in bacillus subtilis. psrfa was prominent in the unique property of inducer-free activity that is closely correlated with cell density. here, using green fluorescent protein (gfp) as the reporter protein, psrfa was optimized by shortening its sequences and changing the nucleotides at the conserved regions of -35 -15 and -10 regions, obtaining a library of psrf ...201627426133
design, synthesis and biological evaluation of novel azaspiro analogs of linezolid as antibacterial and antitubercular agents.the design, synthesis and antimicrobial evaluation of a novel series of azaspiro analogues of linezolid (1) have been described. linezolid comprises of a morpholine ring which is known for its metabolism-related liabilities. therefore, the key modification made in the linezolid structure was the replacement of morpholine moiety with its bioisostere, 2-oxa-6-azaspiro[3.3]heptane. furthermore, the replacement of n-acetyl terminal of 1 with various aromatic or aliphatic functionalities was carried ...201627423637
use of raman spectroscopy and phase-contrast microscopy to characterize cold atmospheric plasma inactivation of individual bacterial spores.raman spectroscopy and phase-contrast microscopy were used to examine calcium dipicolinate (cadpa) levels and rates of nutrient and nonnutrient germination of multiple individual bacillus subtilis spores treated with cold atmospheric plasma (cap). major results for this work include the following: (i) >5 logs of spores deposited on glass surfaces were inactivated by cap treatment for 3 min, while deposited spores placed inside an impermeable plastic bag were inactivated only ∼2 logs in 30 min; ( ...201627422840
multi-loaded ceramic beads/matrix scaffolds obtained by combining ionotropic and freeze gelation for sustained and tuneable vancomycin release.for a targeted release against bacteria-associated bone diseases (osteomyelitis) ceramic beads with a high drug loading capacity, loaded with vancomycin as model antibiotic, are synthesized as drug carrier and successfully incorporated in an open porous hydroxyapatite matrix scaffold via freeze gelation to prevent bead migration at the implantation site and to extend drug release. we demonstrate that the quantity of loaded drug by the hydroxyapatite and β-tricalcium phosphate beads, produced by ...201627287153
enhanced production of butanol and acetoin by heterologous expression of an acetolactate decarboxylase in clostridium acetobutylicum.butanol is an important industrial chemical and an attractive transportation fuel. however, the deficiency of reducing equivalents nad(p)h in butanol fermentation results in a large quantity of oxidation products, which is a major problem limiting the atom economy and economic viability of bio-butanol processes. here, we integrated the butanol fermentation process with a nadh-generating, acetoin biosynthesis process to improve the butanol production. by overexpressing the α-acetolactate decarbox ...201627285575
combination of xylanase and debranching enzymes specific to wheat arabinoxylan improve the growth performance and gut health of broilers.arabinoxylan (ax) is the major antinutritional factor of wheat. this study evaluated the synergistic effects of xylanase and debranching enzymes (arabinofuranosidase [abf] and feruloyl esterase [fae]) on ax. during in vitro tests, the addition of abf or fae accelerated the hydrolysis of water-soluble ax (we-ax) and water-insoluble ax (wu-ax) and produced more xylan oligosaccharides (xos) than xylanase alone. xos obtained from we-ax stimulated greater proliferation of lactobacillus brevis and bac ...201627285356
visualizing bacillus subtilis during vegetative growth and spore formation.bacillus subtilis is the most commonly used gram-positive bacterium to study cellular processes because of its genetic tractability. in addition, during nutrient limitation, b. subtilis undergoes the development process of spore formation, which is among the simplest examples of cellular differentiation. many aspects of these processes have benefited from fluorescence microscopy. here, we describe basic wide-field fluorescence microscopy techniques to visualize b. subtilis during vegetative grow ...201627283315
probing chromosome dynamics in bacillus subtilis.research over the last two decades has revealed that bacterial genomes are, in fact, highly organized. the goal of future research is to understand the molecular mechanisms underlying bacterial chromosome architecture and dynamics during the cell cycle. here we discuss techniques that can be used with live cells to analyze chromosome structure and segregation in the gram-positive model organism bacillus subtilis.201627283304
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