Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| the oxidosqualene cyclase from the oomycete saprolegnia parasitica synthesizes lanosterol as a single product. | the first committed step of sterol biosynthesis is the cyclisation of 2,3-oxidosqualene to form either lanosterol (la) or cycloartenol (ca). this is catalyzed by an oxidosqualene cyclase (osc). la and ca are subsequently converted into various sterols by a series of enzyme reactions. the specificity of the osc therefore determines the final composition of the end sterols of an organism. despite the functional importance of oscs, the determinants of their specificity are not well understood. in s ... | 2016 | 27881978 |
| sterol synthesis in diverse bacteria. | sterols are essential components of eukaryotic cells whose biosynthesis and function has been studied extensively. sterols are also recognized as the diagenetic precursors of steranes preserved in sedimentary rocks where they can function as geological proxies for eukaryotic organisms and/or aerobic metabolisms and environments. however, production of these lipids is not restricted to the eukaryotic domain as a few bacterial species also synthesize sterols. phylogenomic studies have identified g ... | 2016 | 27446030 |
| planctomycetes as novel source of bioactive molecules. | marine environments are a fruitful source of bioactive compounds some of which are the newest leading drugs in medicinal therapeutics. of particular importance are organisms like sponges and macroalgae and their associated microbiome. planctomycetes, abundant in macroalgae biofilms, are promising producers of bioactive compounds since they share characteristics, like large genomes and complex life cycles, with the most bioactive bacteria, the actinobacteria. furthermore, genome mining revealed t ... | 2016 | 27570520 |
| complete genome of the starch-degrading myxobacteria sandaracinus amylolyticus dsm 53668t. | myxobacteria are members of δ-proteobacteria and are typified by large genomes, well-coordinated social behavior, gliding motility, and starvation-induced fruiting body formation. here, we report the 10.33 mb whole genome of a starch-degrading myxobacterium sandaracinus amylolyticus dsm 53668(t) that encodes 8,962 proteins, 56 trna, and two rrna operons. phylogenetic analysis, in silico dna-dna hybridization and average nucleotide identity reveal its divergence from other myxobacterial species a ... | 2016 | 27358428 |
| biosynthesis of α-pyrones. | the α-pyrone moiety is a structural feature found in a huge variety of biologically active metabolites. in recent times new insights into additional biosynthetic mechanisms, yielding in such six-membered unsaturated ester ring residues have been obtained. the purpose of this mini-review is to give a brief overview of α-pyrones and the mechanisms forming the basis of their natural synthesis. especially the chain interconnecting enzymes, showing homology to ketosynthases which catalyze claisen-lik ... | 2016 | 27340449 |
| sibling rivalry in myxococcus xanthus is mediated by kin recognition and a polyploid prophage. | myxobacteria form complex social communities that elicit multicellular behaviors. one such behavior is kin recognition, in which cells identify siblings via their polymorphic traa cell surface receptor, to transiently fuse outer membranes and exchange their contents. in addition, outer membrane exchange (ome) regulates behaviors, such as inhibition of wild-type myxococcus xanthus (dk1622) from swarming. here we monitored the fate of motile cells and surprisingly found they were killed by nonmoti ... | 2016 | 26787762 |
| myxobacteria: moving, killing, feeding, and surviving together. | myxococcus xanthus, like other myxobacteria, is a social bacterium that moves and feeds cooperatively in predatory groups. on surfaces, rod-shaped vegetative cells move in search of the prey in a coordinated manner, forming dynamic multicellular groups referred to as swarms. within the swarms, cells interact with one another and use two separate locomotion systems. adventurous motility, which drives the movement of individual cells, is associated with the secretion of slime that forms trails at ... | 2016 | 27303375 |
| a minimal threshold of c-di-gmp is essential for fruiting body formation and sporulation in myxococcus xanthus. | generally, the second messenger bis-(3'-5')-cyclic dimeric gmp (c-di-gmp) regulates the switch between motile and sessile lifestyles in bacteria. here, we show that c-di-gmp is an essential regulator of multicellular development in the social bacterium myxococcus xanthus. in response to starvation, m. xanthus initiates a developmental program that culminates in formation of spore-filled fruiting bodies. we show that c-di-gmp accumulates at elevated levels during development and that this increas ... | 2016 | 27214040 |
| metagenomic analysis from the interior of a speleothem in tjuv-ante's cave, northern sweden. | speleothems are secondary mineral deposits normally formed by water supersaturated with calcium carbonate percolating into underground caves, and are often associated with low-nutrient and mostly non-phototrophic conditions. tjuv-ante's cave is a shallow-depth cave formed by the action of waves, with granite and dolerite as major components, and opal-a and calcite as part of the speleothems, making it a rare kind of cave. we generated two dna shotgun sequencing metagenomic datasets from the inte ... | 2016 | 26985997 |
| genome analysis of the fruiting body-forming myxobacterium chondromyces crocatus reveals high potential for natural product biosynthesis. | here, we report the complete genome sequence of the type strain of the myxobacterial genus chondromyces, chondromyces crocatus cm c5. it presents one of the largest prokaryotic genomes featuring a single circular chromosome and no plasmids. analysis revealed an enlarged set of trna genes, along with reduced pressure on preferred codon usage compared to that of other bacterial genomes. the large coding capacity and the plethora of encoded secondary metabolite biosynthetic gene clusters are in lin ... | 2016 | 26773087 |
| in depth analysis of the mechanism of action of metal-dependent sigma factors: characterization of core2 from myxococcus xanthus. | extracytoplasmic function sigma factors represent the third pillar of signal-transduction mechanisms in bacteria. the variety of stimuli they recognize and mechanisms of action they use have allowed their classification into more than 50 groups. we have characterized core2 from myxococcus xanthus, which belongs to group ecf44 and upregulates the expression of two genes when it is activated by cadmium and zinc. sigma factors of this group contain a cys-rich domain (crd) at the c terminus which is ... | 2016 | 26951374 |
| heterologous production of the marine myxobacterial antibiotic haliangicin and its unnatural analogues generated by engineering of the biochemical pathway. | despite their fastidious nature, marine myxobacteria have considerable genetic potential to produce novel secondary metabolites. the marine myxobacterium haliangium ochraceum smp-2 produces the antifungal polyketide haliangicin (1), but its productivity is unsatisfactory. the biosynthetic gene cluster hli (47.8 kbp) associated with 1 was identified and heterologously expressed in myxococcus xanthus to permit the production of 1 with high efficiency (tenfold greater amount and threefold faster in ... | 2016 | 26915413 |
| genetic engineering and heterologous expression of the disorazol biosynthetic gene cluster via red/et recombineering. | disorazol, a macrocyclic polykitide produced by the myxobacterium sorangium cellulosum so ce12 and it is reported to have potential cytotoxic activity towards several cancer cell lines, including multi-drug resistant cells. the disorazol biosynthetic gene cluster (dis) from sorangium cellulosum (so ce12) was identified by transposon mutagenesis and cloned in a bacterial artificial chromosome (bac) library. the 58-kb dis core gene cluster was reconstituted from bacs via red/et recombineering and ... | 2016 | 26875499 |
| evidence for an iterative module in chain elongation on the azalomycin polyketide synthase. | the assembly-line synthases that produce bacterial polyketide natural products follow a modular paradigm in which each round of chain extension is catalysed by a different set or module of enzymes. examples of deviation from this paradigm, in which a module catalyses either multiple extensions or none are of interest from both a mechanistic and an evolutionary viewpoint. we present evidence that in the biosynthesis of the 36-membered macrocyclic aminopolyol lactones (marginolactones) azalomycin ... | 2016 | 27829923 |
| understanding the structure and function of bacterial expansins: a prerequisite towards practical applications for the bioenergy and agricultural industries. | since the publication of a landmark article on the structure of exlx1 from bacillus subtilis in 2011, our knowledge of bacterial expansins has steadily increased and our view and understanding of these enigmatic proteins has advanced with relation to their structure, phylogenetic relationships and substrate interaction, although the molecular basis for their mechanism of action remains to be determined. lignocellulosic material represents a source of fermentable sugars for the production of biof ... | 2016 | 27365165 |
| identification of the sfp-type pptase eppa from the lichenized fungus evernia prunastri. | in the last decades, natural products from lichens have gained more interest for pharmaceutical application due to the broad range of their biological activity. however, isolation of the compounds of interest directly from the lichen is neither feasible nor sustainable due to slow growth of many lichens. in order to develop a pipeline for heterologous expression of lichen biosynthesis gene clusters and thus the sustainable production of their bioactive compounds we have identified and characteri ... | 2016 | 26784935 |
| establishing a reference array for the cs-αβ superfamily of defensive peptides. | "invertebrate defensins" belong to the cysteine-stabilized alpha-beta (cs-αβ), also known as the scorpion toxin-like, superfamily. some other peptides belonging to this superfamily of defensive peptides are indistinguishable from "defensins," but have been assigned other names, making it unclear what, if any, criteria must be met to qualify as an "invertebrate defensin." in addition, there are other groups of defensins in invertebrates and vertebrates that are considered to be evolutionarily unr ... | 2016 | 27863510 |
| neutral and phospholipids of the myxococcus xanthus lipodome during fruiting body formation and germination. | myxobacteria are well-known for their complex life cycle, including the formation of spore-filled fruiting bodies. the model organism myxococcus xanthus exhibits a highly complex composition of neutral and phospholipids, including triacylglycerols (tags), diacylglycerols (dags), phosphatidylethanolamines (pes), phosphatidylglycerols (pgs), cardiolipins (cls), and sphingolipids, including ceramides (cers) and ceramide phosphoinositols (cer-pis). in addition, ether lipids have been shown to be inv ... | 2015 | 26162876 |
| pseudomonas putida-a versatile host for the production of natural products. | the biosynthesis of natural products by heterologous expression of biosynthetic pathways in amenable production strains enables biotechnological access to a variety of valuable compounds by conversion of renewable resources. pseudomonas putida has emerged as a microbial laboratory work horse, with elaborated techniques for cultivation and genetic manipulation available. beyond that, this bacterium offers several particular advantages with regard to natural product biosynthesis, notably a versati ... | 2015 | 26099332 |
| archaeal type iv pili and their involvement in biofilm formation. | type iv pili are ancient proteinaceous structures present on the cell surface of species in nearly all bacterial and archaeal phyla. these filaments, which are required for a diverse array of important cellular processes, are assembled employing a conserved set of core components. while type iv pilins, the structural subunits of pili, share little sequence homology, their signal peptides are structurally conserved allowing for in silico prediction. recently, in vivo studies in model archaea repr ... | 2015 | 25852657 |
| fast photochemistry of prototypical phytochromes-a species vs. subunit specific comparison. | phytochromes are multi-domain red light photosensor proteins, which convert red light photons to biological activity utilizing the multitude of structural and chemical reactions. the steady increase in structural information obtained from various bacteriophytochromes has increased understanding about the functional mechanism of the photochemical processes of the phytochromes. furthermore, a number of spectroscopic studies have revealed kinetic information about the light-induced reactions. the s ... | 2015 | 26779488 |
| draft genome sequence of nonomuraea sp. tp-a0861, a producer of myxochelin a. | nonomuraea sp. tp-a0861 produces the nonribosomal peptide myxochelin a, which is known as a microbial siderophore. here, we report its draft genome sequence. the genome contains at least three nonribosomal peptide synthetase gene clusters, one of which is proposed to be responsible for the biosynthesis of myxochelin a. | 2015 | 26659677 |
| iterative polyketide biosynthesis by modular polyketide synthases in bacteria. | modular polyketide synthases (type i pkss) in bacteria are responsible for synthesizing a significant percentage of bioactive natural products. this group of synthases has a characteristic modular organization, and each module within a pks carries out one cycle of polyketide chain elongation; thus each module is non-iterative in function. it was possible to predict the basic structure of a polyketide product from the module organization of the pkss, since there generally existed a co-linearity b ... | 2015 | 26549236 |
| iterative polyketide biosynthesis by modular polyketide synthases in bacteria. | modular polyketide synthases (type i pkss) in bacteria are responsible for synthesizing a significant percentage of bioactive natural products. this group of synthases has a characteristic modular organization, and each module within a pks carries out one cycle of polyketide chain elongation; thus each module is non-iterative in function. it was possible to predict the basic structure of a polyketide product from the module organization of the pkss, since there generally existed a co-linearity b ... | 2015 | 26549236 |
| bacterial genome mining of enzymatic tools for alkyne biosynthesis. | the alkyne is an important functionality widely used in material science, pharmaceutical science, and chemical biology, but the importance of this functionality is contrasted by the very limited number of enzymes known to be involved in alkyne biosynthesis. we recently reported the first known carrier protein-dependent pathway for terminal alkyne formation, and in silico analysis suggested that this mechanism could be widespread in bacteria. in this paper, we screened additional homologous gene ... | 2015 | 26441143 |
| the wolbachia wo bacteriophage proteome in the aedes albopictus c/wstr1 cell line: evidence for lytic activity? | wolbachia pipientis (rickettsiales), an obligate intracellular alphaproteobacterium in insects, manipulates host reproduction to maximize invasion of uninfected insect populations. modification of host population structure has potential applications for control of pest species, particularly if wolbachia can be maintained, manipulated, and genetically engineered in vitro. although wolbachia maintains an obligate mutualism with genome stability in nematodes, arthropods can be co-infected with dist ... | 2015 | 26427709 |
| the wolbachia wo bacteriophage proteome in the aedes albopictus c/wstr1 cell line: evidence for lytic activity? | wolbachia pipientis (rickettsiales), an obligate intracellular alphaproteobacterium in insects, manipulates host reproduction to maximize invasion of uninfected insect populations. modification of host population structure has potential applications for control of pest species, particularly if wolbachia can be maintained, manipulated, and genetically engineered in vitro. although wolbachia maintains an obligate mutualism with genome stability in nematodes, arthropods can be co-infected with dist ... | 2015 | 26427709 |
| bacterial d-amino acid oxidases: recent findings and future perspectives. | d-amino acid oxidase (dao) is a flavin enzyme that catalyzes the oxidative deamination of d-amino acids. this enzyme has been studied extensively both biochemically and structurally as a model for the oxidase-dehydrogenase class of flavoproteins. this enzyme also has various applications, such as the determination of d-amino acids and production of building blocks for a number of pharmaceuticals. dao has been found mainly in eukaryotic organisms and has been suggested to play a significant role ... | 2015 | 25996186 |
| active site and laminarin binding in glycoside hydrolase family 55. | the carbohydrate active enzyme (cazy) database indicates that glycoside hydrolase family 55 (gh55) contains both endo- and exo-β-1,3-glucanases. the founding structure in the gh55 is pclam55a from the white rot fungus phanerochaete chrysosporium (ishida, t., fushinobu, s., kawai, r., kitaoka, m., igarashi, k., and samejima, m. (2009) crystal structure of glycoside hydrolase family 55 β-1,3-glucanase from the basidiomycete phanerochaete chrysosporium. j. biol. chem. 284, 10100-10109). here, we pr ... | 2015 | 25752603 |
| amym, a novel maltohexaose-forming α-amylase from corallococcus sp. strain egb. | a novel α-amylase, amym, was purified from the culture supernatant of corallococcus sp. strain egb. amym is a maltohexaose-forming exoamylase with an apparent molecular mass of 43 kda. based on the results of matrix-assisted laser desorption ionization-time of flight mass spectrometry and peptide mass fingerprinting of amym and by comparison to the genome sequence of corallococcus coralloides dsm 2259, the amym gene was identified and cloned into escherichia coli. amym encodes a secretory amylas ... | 2015 | 25576603 |
| microbial consortium associated with the antarctic marine ciliate euplotes focardii: an investigation from genomic sequences. | we report the characterization of the bacterial consortium associated to euplotes focardii, a strictly psychrophilic marine ciliate that was maintained in laboratory cultures at 4 °c after its first isolation from terra nova bay, in antarctica. by illumina genome analyser, we obtained 11,179 contigs of potential prokaryotic origin and classified them according to the ncbi's prokaryotic attributes table. the majority of these sequences correspond to either bacteroidetes (16 %) or proteobacteria ( ... | 2015 | 25704316 |
| indole is an essential herbivore-induced volatile priming signal in maize. | herbivore-induced volatile organic compounds prime non-attacked plant tissues to respond more strongly to subsequent attacks. however, the key volatiles that trigger this primed state remain largely unidentified. in maize, the release of the aromatic compound indole is herbivore-specific and occurs earlier than other induced responses. we therefore hypothesized that indole may be involved in airborne priming. using indole-deficient mutants and synthetic indole dispensers, we show that herbivore- ... | 2015 | 25683900 |
| first genomic insights into members of a candidate bacterial phylum responsible for wastewater bulking. | filamentous cells belonging to the candidate bacterial phylum ksb3 were previously identified as the causative agent of fatal filament overgrowth (bulking) in a high-rate industrial anaerobic wastewater treatment bioreactor. here, we obtained near complete genomes from two ksb3 populations in the bioreactor, including the dominant bulking filament, using differential coverage binning of metagenomic data. fluorescence in situ hybridization with 16s rrna-targeted probes specific for the two popula ... | 2015 | 25650158 |
| cyclic di-gmp regulates type iv pilus-dependent motility in myxococcus xanthus. | the nucleotide-based second messenger bis-(3'-5')-cyclic dimeric gmp (c-di-gmp) is involved in regulating a plethora of processes in bacteria that are typically associated with lifestyle changes. myxococcus xanthus undergoes major lifestyle changes in response to nutrient availability, with the formation of spreading colonies in the presence of nutrients and spore-filled fruiting bodies in the absence of nutrients. here, we investigated the function of c-di-gmp in m. xanthus and show that this b ... | 2015 | 26124238 |
| cyclic di-gmp regulates type iv pilus-dependent motility in myxococcus xanthus. | the nucleotide-based second messenger bis-(3'-5')-cyclic dimeric gmp (c-di-gmp) is involved in regulating a plethora of processes in bacteria that are typically associated with lifestyle changes. myxococcus xanthus undergoes major lifestyle changes in response to nutrient availability, with the formation of spreading colonies in the presence of nutrients and spore-filled fruiting bodies in the absence of nutrients. here, we investigated the function of c-di-gmp in m. xanthus and show that this b ... | 2015 | 26124238 |
| genome-wide analysis of myxobacterial two-component systems: genome relatedness and evolutionary changes. | two-component systems (tcss) are abundant prokaryotic signaling pathways, whose evolution is of particular importance because of their role in bacterial pathogenicity. comparative genomics can provide important insights into the evolution of these genes, but inferences are dependent on the relatedness of the compared genomes. this study investigated the relationship between evolutionary distance and tcs evolution in myxobacterial genomes, of which there are several sequenced examples, of varying ... | 2015 | 26463047 |
| devi is an evolutionarily young negative regulator of myxococcus xanthus development. | during starvation-induced development of myxococcus xanthus, thousands of rod-shaped cells form mounds in which they differentiate into spores. the dev locus includes eight genes followed by clustered regularly interspaced short palindromic repeats (crisprs), comprising a crispr-cas system (cas stands for crispr associated) typically involved in rna interference. mutations in devs or devr of a lab reference strain permit mound formation but impair sporulation. we report that natural isolates of ... | 2015 | 25645563 |
| can oral infection be a risk factor for alzheimer's disease? | alzheimer's disease (ad) is a scourge of longevity that will drain enormous resources from public health budgets in the future. currently, there is no diagnostic biomarker and/or treatment for this most common form of dementia in humans. ad can be of early familial-onset or sporadic with a late-onset. apart from the two main hallmarks, amyloid-beta and neurofibrillary tangles, inflammation is a characteristic feature of ad neuropathology. inflammation may be caused by a local central nervous sys ... | 2015 | 26385886 |
| approach to analyze the diversity of myxobacteria in soil by semi-nested pcr-denaturing gradient gel electrophoresis (dgge) based on taxon-specific gene. | the genotypic diversity of insoluble macromolecules degraded myxobacteria, provided an opportunity to discover new bacterial resources and find new ecological functions. in this study, we developed a semi-nested-pcr-denaturing gradient gel electrophoresis (dgge) strategy to determine the presence and genotypic diversity of myxobacteria in soil. after two rounds of pcr with myxobacteria-specific primers, an 194 bp fragment of mgla, a key gene involved in gliding motility, suitable for dgge was ob ... | 2014 | 25280065 |
| unlocking the mystery of the hard-to-sequence phage genome: pap1 methylome and bacterial immunity. | whole-genome sequencing is an important method to understand the genetic information, gene function, biological characteristics and survival mechanisms of organisms. sequencing large genomes is very simple at present. however, we encountered a hard-to-sequence genome of pseudomonas aeruginosa phage pap1. shotgun sequencing method failed to complete the sequence of this genome. | 2014 | 25233860 |
| novel lant associated lantibiotic clusters identified by genome database mining. | frequent use of antibiotics has led to the emergence of antibiotic resistance in bacteria. lantibiotic compounds are ribosomally synthesized antimicrobial peptides against which bacteria are not able to produce resistance, hence making them a good alternative to antibiotics. nisin is the oldest and the most widely used lantibiotic, in food preservation, without having developed any significant resistance against it. having their antimicrobial potential and a limited number, there is a need to id ... | 2014 | 24621781 |
| new mini- zincin structures provide a minimal scaffold for members of this metallopeptidase superfamily. | the acel_2062 protein from acidothermus cellulolyticus is a protein of unknown function. initial sequence analysis predicted that it was a metallopeptidase from the presence of a motif conserved amongst the asp-zincins, which are peptidases that contain a single, catalytic zinc ion ligated by the histidines and aspartic acid within the motif (hexxhxxgxxd). the acel_2062 protein was chosen by the joint center for structural genomics for crystal structure determination to explore novel protein seq ... | 2014 | 24383880 |
| diversity of epothilone producers among sorangium strains in producer-positive soil habitats. | large-scale surveys show that the anti-tumour compounds known as epothilones are produced by only a small proportion of sorangium strains, thereby greatly hampering the research and development of these valuable compounds. in this study, to investigate the niche diversity of epothilone-producing sorangium strains, we re-surveyed four soil samples where epothilone producers were previously found. compared with the < 2.5% positive strains collected from different places, epothilone producers compr ... | 2014 | 24308800 |
| diversity of epothilone producers among sorangium strains in producer-positive soil habitats. | large-scale surveys show that the anti-tumour compounds known as epothilones are produced by only a small proportion of sorangium strains, thereby greatly hampering the research and development of these valuable compounds. in this study, to investigate the niche diversity of epothilone-producing sorangium strains, we re-surveyed four soil samples where epothilone producers were previously found. compared with the < 2.5% positive strains collected from different places, epothilone producers compr ... | 2014 | 24308800 |
| chemosensory regulation of a heat-repeat protein couples aggregation and sporulation in myxococcus xanthus. | chemosensory systems are complex, highly modified two-component systems (tcs) used by bacteria to control various biological functions ranging from motility to sporulation. chemosensory systems and tcs both modulate phosphorelays comprised of histidine kinases and response regulators, some of which are single-domain response regulators (sd-rrs) such as chey. in this study, we have identified and characterized the che7 chemosensory system of myxococcus xanthus, a common soil bacterium which displ ... | 2014 | 24957622 |
| searching for convergent evolution in manganese superoxidase dismutase using hydrophobic cluster analysis. | there are numerous examples of convergent evolution in nature. major ecological adaptations such as flight, loss of limbs in vertebrates, pesticide resistance, adaptation to a parasitic way of life, etc., have all evolved more than once, as seen by their analogous functions in separate taxa. but what about protein evolution? does the environment have a strong enough influence on intracellular processes that enzymes and other functional proteins play, to evolve similar functional roles separately ... | 2014 | 25071412 |
| predation by myxococcus xanthus induces bacillus subtilis to form spore-filled megastructures. | biofilm formation is a common mechanism for surviving environmental stress and can be triggered by both intraspecies and interspecies interactions. prolonged predator-prey interactions between the soil bacterium myxococcus xanthus and bacillus subtilis were found to induce the formation of a new type of b. subtilis biofilm, termed megastructures. megastructures are tree-like brachiations that are as large as 500 μm in diameter, are raised above the surface between 150 and 200 μm, and are filled ... | 2014 | 25326308 |
| predation by myxococcus xanthus induces bacillus subtilis to form spore-filled megastructures. | biofilm formation is a common mechanism for surviving environmental stress and can be triggered by both intraspecies and interspecies interactions. prolonged predator-prey interactions between the soil bacterium myxococcus xanthus and bacillus subtilis were found to induce the formation of a new type of b. subtilis biofilm, termed megastructures. megastructures are tree-like brachiations that are as large as 500 μm in diameter, are raised above the surface between 150 and 200 μm, and are filled ... | 2014 | 25326308 |
| evolution and diversity of the ras superfamily of small gtpases in prokaryotes. | the ras superfamily of small gtpases are single domain nucleotide-dependent molecular switches that act as highly tuned regulators of complex signal transduction pathways. originally identified in eukaryotes for their roles in fundamental cellular processes including proliferation, motility, polarity, nuclear transport, and vesicle transport, recent studies have revealed that single domain gtpases also control complex functions such as cell polarity, motility, predation, development and antibiot ... | 2014 | 25480683 |
| evolution and diversity of the ras superfamily of small gtpases in prokaryotes. | the ras superfamily of small gtpases are single domain nucleotide-dependent molecular switches that act as highly tuned regulators of complex signal transduction pathways. originally identified in eukaryotes for their roles in fundamental cellular processes including proliferation, motility, polarity, nuclear transport, and vesicle transport, recent studies have revealed that single domain gtpases also control complex functions such as cell polarity, motility, predation, development and antibiot ... | 2014 | 25480683 |
| a comprehensive insight into the lipid composition of myxococcus xanthus by uplc-esi-ms. | analysis of whole cell lipid extracts of bacteria by means of ultra-performance (up)lc-ms allows a comprehensive determination of the lipid molecular species present in the respective organism. the data allow conclusions on its metabolic potential as well as the creation of lipid profiles, which visualize the organism's response to changes in internal and external conditions. herein, we describe: i) a fast reversed phase uplc-esi-ms method suitable for detection and determination of individual l ... | 2014 | 25332432 |
| distribution, diversity, and activities of sulfur dioxygenases in heterotrophic bacteria. | sulfur oxidation by chemolithotrophic bacteria is well known; however, sulfur oxidation by heterotrophic bacteria is often ignored. sulfur dioxygenases (sdos) (ec 1.13.11.18) were originally found in the cell extracts of some chemolithotrophic bacteria as glutathione (gsh)-dependent sulfur dioxygenases. gsh spontaneously reacts with elemental sulfur to generate glutathione persulfide (gssh), and sdos oxidize gssh to sulfite and gsh. however, sdos have not been characterized for bacteria, includi ... | 2014 | 24389926 |
| the functions of dna methylation by ccrm in caulobacter crescentus: a global approach. | dna methylation is involved in a diversity of processes in bacteria, including maintenance of genome integrity and regulation of gene expression. here, using caulobacter crescentus as a model, we exploit genome-wide experimental methods to uncover the functions of ccrm, a dna methyltransferase conserved in most alphaproteobacteria. using single molecule sequencing, we provide evidence that most ccrm target motifs (gantc) switch from a fully methylated to a hemi-methylated state when they are rep ... | 2014 | 24398711 |
| the phosphopantetheinyl transferases: catalysis of a post-translational modification crucial for life. | covering: up to 2013. although holo-acyl carrier protein synthase, acps, a phosphopantetheinyl transferase (pptase), was characterized in the 1960s, it was not until the publication of the landmark paper by lambalot et al. in 1996 that pptases garnered wide-spread attention being classified as a distinct enzyme superfamily. in the past two decades an increasing number of papers have been published on pptases ranging from identification, characterization, structure determination, mutagenesis, inh ... | 2014 | 24292120 |
| a highly stable d-amino acid oxidase of the thermophilic bacterium rubrobacter xylanophilus. | d-amino acid oxidase (dao) is a biotechnologically attractive enzyme that can be used in a variety of applications, but its utility is limited by its relatively poor stability. a search of a bacterial genome database revealed a gene encoding a protein homologous to dao in the thermophilic bacterium rubrobacter xylanophilus (rxdao). the recombinant protein expressed in escherichia coli was a monomeric protein containing noncovalently bound flavin adenine dinucleotide as a cofactor. this protein e ... | 2014 | 25217016 |
| car: contig assembly of prokaryotic draft genomes using rearrangements. | next generation sequencing technology has allowed efficient production of draft genomes for many organisms of interest. however, most draft genomes are just collections of independent contigs, whose relative positions and orientations along the genome being sequenced are unknown. although several tools have been developed to order and orient the contigs of draft genomes, more accurate tools are still needed. | 2014 | 25431302 |
| a type iv translocated legionella cysteine phytase counteracts intracellular growth restriction by phytate. | the causative agent of legionnaires' pneumonia, legionella pneumophila, colonizes diverse environmental niches, including biofilms, plant material, and protozoa. in these habitats, myo-inositol hexakisphosphate (phytate) is prevalent and used as a phosphate storage compound or as a siderophore. l. pneumophila replicates in protozoa and mammalian phagocytes within a unique "legionella-containing vacuole." the bacteria govern host cell interactions through the icm/dot type iv secretion system (t4s ... | 2014 | 25339170 |
| complete genome sequence of producer of the glycopeptide antibiotic aculeximycin kutzneria albida dsm 43870t, a representative of minor genus of pseudonocardiaceae. | kutzneria is a representative of a rarely observed genus of the family pseudonocardiaceae. kutzneria species were initially placed in the streptosporangiaceae genus and later reconsidered to be an independent genus of the pseudonocardiaceae. kutzneria albida is one of the eight known members of the genus. this strain is a unique producer of the glycosylated polyole macrolide aculeximycin which is active against both bacteria and fungi. kutzneria albida genome sequencing and analysis allow a deep ... | 2014 | 25301375 |
| mining the metabiome: identifying novel natural products from microbial communities. | microbial-derived natural products provide the foundation for most of the chemotherapeutic arsenal available to contemporary medicine. in the face of a dwindling pipeline of new lead structures identified by traditional culturing techniques and an increasing need for new therapeutics, surveys of microbial biosynthetic diversity across environmental metabiomes have revealed enormous reservoirs of as yet untapped natural products chemistry. in this review, we touch on the historical context of mic ... | 2014 | 25237864 |
| structural and biochemical analysis of a unique phosphatase from bdellovibrio bacteriovorus reveals its structural and functional relationship with the protein tyrosine phosphatase class of phytase. | bdellovibrio bacteriovorus is an unusual δ-proteobacterium that invades and preys on other gram-negative bacteria and is of potential interest as a whole cell therapeutic against pathogens of man, animals and crops. ptps (protein tyrosine phosphatases) are an important class of enzyme involved in desphosphorylating a variety of substrates, often with implications in cell signaling. the b. bacteriovorus open reading frame bd1204 is predicted to encode a ptp of unknown function. bd1204 is both str ... | 2014 | 24718691 |
| discovering new bioactive molecules from microbial sources. | there is an increased need for new drug leads to treat diseases in humans, animals and plants. a dramatic example is represented by the need for novel and more effective antibiotics to combat multidrug-resistant microbial pathogens. natural products represent a major source of approved drugs and still play an important role in supplying chemical diversity, despite a decreased interest by large pharmaceutical companies. novel approaches must be implemented to decrease the chances of rediscovering ... | 2014 | 24661414 |
| role of the bicarbonate-responsive soluble adenylyl cyclase in ph sensing and metabolic regulation. | the evolutionarily conserved soluble adenylyl cyclase (sac, adcy10) was recently identified as a unique source of camp in the cytoplasm and the nucleus. its activity is regulated by bicarbonate and fine-tuned by calcium. as such, and in conjunction with carbonic anhydrase (ca), sac constitutes an hco(-) 3/co(-) 2/ph sensor. in both alpha-intercalated cells of the collecting duct and the clear cells of the epididymis, sac is expressed at significant level and involved in ph homeostasis via apical ... | 2014 | 24575049 |
| improved seamless mutagenesis by recombineering using ccdb for counterselection. | recombineering, which is the use of homologous recombination for dna engineering in escherichia coli, usually uses antibiotic selection to identify the intended recombinant. when combined in a second step with counterselection using a small molecule toxin, seamless products can be obtained. here, we report the advantages of a genetic strategy using ccdb as the counterselectable agent. expression of ccdb is toxic to e. coli in the absence of the ccda antidote so counterselection is initiated by t ... | 2014 | 24369425 |
| improved seamless mutagenesis by recombineering using ccdb for counterselection. | recombineering, which is the use of homologous recombination for dna engineering in escherichia coli, usually uses antibiotic selection to identify the intended recombinant. when combined in a second step with counterselection using a small molecule toxin, seamless products can be obtained. here, we report the advantages of a genetic strategy using ccdb as the counterselectable agent. expression of ccdb is toxic to e. coli in the absence of the ccda antidote so counterselection is initiated by t ... | 2014 | 24369425 |
| the myxocoumarins a and b from stigmatella aurantiaca strain myx-030. | the myxobacterial strain stigmatella aurantiaca myx-030 was selected as promising source for the discovery of new biologically active natural products by our screening methodology. the isolation, structure elucidation and initial biological evaluation of the myxocoumarins derived from this strain are described in this work. these compounds comprise an unusual structural framework and exhibit remarkable antifungal properties. | 2013 | 24367422 |
| physiological and proteomic responses of diploid and tetraploid black locust (robinia pseudoacacia l.) subjected to salt stress. | tetraploid black locust (robinia pseudoacacia l.) is adaptable to salt stress. here, we compared morphological, physiological, ultrastructural, and proteomic traits of leaves in tetraploid black locust and its diploid relatives under salt stress. the results showed that diploid (2×) plants suffered from greater negative effects than those of tetraploid (4×) plants. after salt treatment, plant growth was inhibited, photosynthesis was reduced, reactive oxygen species, malondialdehyde content, and ... | 2013 | 24129170 |
| a practical synthesis of long-chain iso-fatty acids (iso-c12-c19) and related natural products. | a gram-scale synthesis of terminally-branched iso-fatty acids (iso-c12-c19) was developed commencing with methyl undec-10-enoate (methyl undecylenate) (for iso-c12-c14) or the c15 and c16 lactones pentadecanolide (for iso-c15-c17) and hexadecanolide (for iso-c18-c19). central to the approaches outlined is the two-step construction of the terminal isopropyl group through addition of methylmagnesium bromide to the ester/lactones and selective reduction of the resulting tertiary alcohols. thus, the ... | 2013 | 24062846 |
| synthesis and biological activities of the respiratory chain inhibitor aurachin d and new ring versus chain analogues. | aurachins are myxobacterial 3-farnesyl-4(1h)-quinolone derived compounds initially described as respiratory chain inhibitors, more specifically as inhibitors of various cytochrome complexes. they are also known as potent antibiotic compounds. we describe herein the first synthesis of aurachin d through a key conrad-limpach reaction. the same strategy was used to reach some ring as opposed to chain analogues, allowing for the description of structure-activity relationships. biological screening o ... | 2013 | 23946854 |
| set-domain bacterial effectors target heterochromatin protein 1 to activate host rdna transcription. | transcription of rrna genes (rdnas) in the nucleolus is regulated by epigenetic chromatin modifications including histone h3 lysine (de)methylation. here we show that legas4, a legionella pneumophila type iv secretion system (tfss) effector, is targeted to specific rdna chromatin regions in the host nucleolus. legas4 promotes rdna transcription, through its set-domain (named after drosophila su(var)3-9, enhancer of zeste [e(z)], and trithorax [trx]) histone lysine methyltransferase (hkmtase) act ... | 2013 | 23797873 |
| high-titer heterologous production in e. coli of lyngbyatoxin, a protein kinase c activator from an uncultured marine cyanobacterium. | many chemically complex cyanobacterial polyketides and nonribosomal peptides are of great pharmaceutical interest, but the levels required for exploitation are difficult to achieve from native sources. here we develop a framework for the expression of these multifunctional cyanobacterial assembly lines in escherichia coli using the lyngbyatoxin biosynthetic pathway, derived from a marine microbial assemblage dominated by the cyanobacterium moorea producens. heterologous expression of this pathwa ... | 2013 | 23751865 |
| separate origins of ice-binding proteins in antarctic chlamydomonas species. | the green alga chlamydomonas raudensis is an important primary producer in a number of ice-covered lakes and ponds in antarctica. a c. raudensis isolate (uwo241) from lake bonney in the mcmurdo dry valleys, like many other antarctic algae, was found to secrete ice-binding proteins (ibps), which appear to be essential for survival in icy environments. the ibps of several antarctic algae (diatoms, a prymesiophyte, and a prasinophyte) are similar to each other (here designated as type i ibps) and h ... | 2013 | 23536869 |
| identification of a cyclosporine-specific p450 hydroxylase gene through targeted cytochrome p450 complement (cypome) disruption in sebekia benihana. | it was previously proposed that regio-specific hydroxylation of an immunosuppressive cyclosporine (csa) at the 4th n-methyl leucine is mediated by cytochrome p450 hydroxylase (cyp) in the rare actinomycete sebekia benihana. this modification is thought to be the reason for the hair growth-promoting side effect without the immunosuppressive activity of csa. through s. benihana genome sequencing and in silico analysis, we identified the complete cytochrome p450 complement (cypome) of s. benihana, ... | 2013 | 23354713 |
| a laterally acquired galactose oxidase-like gene is required for aerial development during osmotic stress in streptomyces coelicolor. | phylogenetic reconstruction revealed that most actinobacterial orthologs of s. coelicolor sco2837, encoding a metal-dependent galactose oxidase-like protein, are found within streptomyces and were probably acquired by horizontal gene transfer from fungi. disruption of sco2837 (glxa) caused a conditional bld phenotype that could not be reversed by extracellular complementation. studies aimed at characterising the regulation of expression of glxa showed that it is not a target for other bld genes. ... | 2013 | 23326581 |
| a proteomic approach provides new insights into the control of soil-borne plant pathogens by bacillus species. | beneficial microorganisms (also known as biopesticides) are considered to be one of the most promising methods for more rational and safe crop management practices. we used bacillus strains eu07, qst713 and fzb24, and investigated their inhibitory effect on fusarium. bacterial cell cultures, cell-free supernatants and volatiles displayed varying degrees of suppressive effect. proteomic analysis of secreted proteins from eu07 and fzb24 revealed the presence of lytic enzymes, cellulases, proteases ... | 2013 | 23301041 |
| lessons learned from the transformation of natural product discovery to a genome-driven endeavor. | natural product discovery is currently undergoing a transformation from a phenotype-driven field to a genotype-driven one. the increasing availability of genome sequences, coupled with improved techniques for identifying biosynthetic gene clusters, has revealed that secondary metabolomes are strikingly vaster than previously thought. new approaches to correlate biosynthetic gene clusters with the compounds they produce have facilitated the production and isolation of a rapidly growing collection ... | 2013 | 24142337 |
| lessons learned from the transformation of natural product discovery to a genome-driven endeavor. | natural product discovery is currently undergoing a transformation from a phenotype-driven field to a genotype-driven one. the increasing availability of genome sequences, coupled with improved techniques for identifying biosynthetic gene clusters, has revealed that secondary metabolomes are strikingly vaster than previously thought. new approaches to correlate biosynthetic gene clusters with the compounds they produce have facilitated the production and isolation of a rapidly growing collection ... | 2013 | 24142337 |
| complete genome sequence of myxococcus stipitatus strain dsm 14675, a fruiting myxobacterium. | hallmarks of the myxobacteria include the formation of spore-filled fruiting bodies in response to starvation and synthesis of secondary metabolites. myxococcus stipitatus forms morphologically highly distinct fruiting bodies and produces secondary metabolites with antibiotic or cytotoxic activities. here, we present the 10.35-mb genome sequence of m. stipitatus strain dsm 14675. | 2013 | 23516218 |
| type i pyridoxal 5'-phosphate dependent enzymatic domains embedded within multimodular nonribosomal peptide synthetase and polyketide synthase assembly lines. | pyridoxal 5'-phosphate (plp)-dependent enzymes of fold type i, the most studied structural class of the plp-dependent enzyme superfamily, are known to exist as stand-alone homodimers or homotetramers. these enzymes have been found also embedded in multimodular and multidomain assembly lines involved in the biosynthesis of polyketides (pks) and nonribosomal peptides (nrps). the aim of this work is to provide a proteome-wide view of the distribution and characteristics of type i domains covalently ... | 2013 | 24148833 |
| phylogenetic analysis of six-domain multi-copper blue proteins. | multicopper blue proteins, composed of several repetitive copper-binding domains similar to one-domain cupredoxin-like proteins, were found in almost all organisms. they are classified into the three different groups, based on their two-, three- or six-domain organization. we found orthologs of chordate six-domain copper-binding proteins in animals, plants, bacteria and archea. the phylogenetic analysis of 183 multicopper blue proteins and their copper-binding sites comparison make us think that ... | 2013 | 23516668 |
| eubacterial spovg homologs constitute a new family of site-specific dna-binding proteins. | a site-specific dna-binding protein was purified from borrelia burgdorferi cytoplasmic extracts, and determined to be a member of the highly conserved spovg family. this is the first time a function has been attributed to any of these ubiquitous bacterial proteins. further investigations into spovg orthologues indicated that the staphylococcus aureus protein also binds dna, but interacts preferentially with a distinct nucleic acid sequence. site-directed mutagenesis and domain swapping between t ... | 2013 | 23818957 |
| pathogenomic inference of virulence-associated genes in leptospira interrogans. | leptospirosis is a globally important, neglected zoonotic infection caused by spirochetes of the genus leptospira. since genetic transformation remains technically limited for pathogenic leptospira, a systems biology pathogenomic approach was used to infer leptospiral virulence genes by whole genome comparison of culture-attenuated leptospira interrogans serovar lai with its virulent, isogenic parent. among the 11 pathogen-specific protein-coding genes in which non-synonymous mutations were foun ... | 2013 | 24098822 |
| veillonella, firmicutes: microbes disguised as gram negatives. | the firmicutes represent a major component of the intestinal microflora. the intestinal firmicutes are a large, diverse group of organisms, many of which are poorly characterized due to their anaerobic growth requirements. although most firmicutes are gram positive, members of the class negativicutes, including the genus veillonella, stain gram negative. veillonella are among the most abundant organisms of the oral and intestinal microflora of animals and humans, in spite of being strict anaerob ... | 2013 | 24976898 |
| production of the cannibalism toxin sdp is a multistep process that requires sdpa and sdpb. | during the early stages of sporulation, a subpopulation of bacillus subtilis cells secrete toxins that kill their genetically identical siblings in a process termed cannibalism. one of these toxins is encoded by the sdpc gene of the sdpabc operon. the active form of the sdp toxin is a 42-amino-acid peptide with a disulfide bond which is processed from an internal fragment of pro-sdpc. the factors required for the processing of pro-sdpc into mature sdp are not known. we provide evidence that pro- ... | 2013 | 23687264 |
| relevance of gc content to the conservation of dna polymerase iii/mismatch repair system in gram-positive bacteria. | the mechanism of dna replication is one of the driving forces of genome evolution. bacterial dna polymerase iii, the primary complex of dna replication, consists of polc and dnae. polc is conserved in gram-positive bacteria, especially in the firmicutes with low gc content, whereas dnae is widely conserved in most gram-negative and gram-positive bacteria. polc contains two domains, the 3'-5'exonuclease domain and the polymerase domain, while dnae only possesses the polymerase domain. accordingly ... | 2013 | 24062730 |
| microbial cytochromes p450: biodiversity and biotechnology. where do cytochromes p450 come from, what do they do and what can they do for us? | the first eukaryote genome revealed three yeast cytochromes p450 (cyps), hence the subsequent realization that some microbial fungal genomes encode these proteins in 1 per cent or more of all genes (greater than 100) has been surprising. they are unique biocatalysts undertaking a wide array of stereo- and regio-specific reactions and so hold promise in many applications. based on ancestral activities that included 14α-demethylation during sterol biosynthesis, it is now seen that cyps are part of ... | 2013 | 23297358 |
| antimicrobial peptides from marine proteobacteria. | after years of inadequate use and the emergence of multidrug resistant (mdr) strains, the efficiency of "classical" antibiotics has decreased significantly. new drugs to fight mdr strains are urgently needed. bacteria hold much promise as a source of unusual bioactive metabolites. however, the potential of marine bacteria, except for actinomycetes and cyanobacteria, has been largely underexplored. in the past two decades, the structures of several antimicrobial compounds have been elucidated in ... | 2013 | 24084784 |
| isolation and identification of myxobacteria from saline-alkaline soils in xinjiang, china. | fifty-eight terrestrial and salt-tolerant myxobacteria were isolated from the saline-alkaline soils collected from xinjiang, china. based on the morphologies and the 16s rrna gene sequences, these isolates were assigned into 6 genera, myxococcus, cystobacter, corallococcus, sorangium, nannocystis and polyangium. all the strains grew better with 1% nacl than without nacl. some myxococcus strains were able to grow at 2% nacl concentration, suggesting that these strains may be particular type of te ... | 2013 | 23936436 |
| direct live imaging of cell-cell protein transfer by transient outer membrane fusion in myxococcus xanthus. | in bacteria, multicellular behaviors are regulated by cell-cell signaling through the exchange of both diffusible and contact-dependent signals. in a multicellular context, myxococcus cells can share outer membrane (om) materials by an unknown mechanism involving the traab genes and gliding motility. using live imaging, we show for the first time that transient contacts between two cells are sufficient to transfer om materials, proteins and lipids, at high efficiency. transfer was associated wit ... | 2013 | 23898400 |
| draft genome of a type 4 pilus defective myxococcus xanthus strain, dzf1. | myxococcus xanthus is a member of the myxococcales order within the deltaproteobacterial subdivision. here, we report the whole-genome shotgun sequence of the type iv pilus (t4p) defective strain dzf1, which includes many genes found in strain dz2 but absent from strain dk1622. | 2013 | 23788552 |
| draft genome sequence of myxococcus xanthus wild-type strain dz2, a model organism for predation and development. | myxococcus xanthus is a member of the myxococcales order within the deltaproteobacteria subdivision. the myxobacteria reside in soil, have relatively large genomes, and display complex life cycles. here, we report the whole-genome shotgun sequence of strain dz2, which includes unique genes not found previously in strain dk1622. | 2013 | 23661486 |
| a modern understanding of the traditional and nontraditional biological functions of angiotensin-converting enzyme. | angiotensin-converting enzyme (ace) is a zinc-dependent peptidase responsible for converting angiotensin i into the vasoconstrictor angiotensin ii. however, ace is a relatively nonspecific peptidase that is capable of cleaving a wide range of substrates. because of this, ace and its peptide substrates and products affect many physiologic processes, including blood pressure control, hematopoiesis, reproduction, renal development, renal function, and the immune response. the defining feature of ac ... | 2013 | 23257181 |
| high-mobility-group a-like card binds to a dna site optimized for affinity and position and to rna polymerase to regulate a light-inducible promoter in myxococcus xanthus. | the card-carg complex controls various cellular processes in the bacterium myxococcus xanthus including fruiting body development and light-induced carotenogenesis. the card n-terminal domain, which defines the large card_cdnl_trcf protein family, binds to carg, a zinc-associated protein that does not bind dna. the card c-terminal domain resembles eukaryotic high-mobility-group a (hmga) proteins, and its dna binding at hooks specifically recognize the minor groove of appropriately spaced at-rich ... | 2013 | 23144251 |
| molecular characterization of podoviral bacteriophages virulent for clostridium perfringens and their comparison with members of the picovirinae. | clostridium perfringens is a gram-positive, spore-forming anaerobic bacterium responsible for human food-borne disease as well as non-food-borne human, animal and poultry diseases. because bacteriophages or their gene products could be applied to control bacterial diseases in a species-specific manner, they are potential important alternatives to antibiotics. consequently, poultry intestinal material, soil, sewage and poultry processing drainage water were screened for virulent bacteriophages th ... | 2012 | 22666499 |
| intra- and interprotein phosphorylation between two-hybrid histidine kinases controls myxococcus xanthus developmental progression. | histidine-aspartate phosphorelay signaling systems are used to couple stimuli to cellular responses. a hallmark feature is the highly modular signal transmission modules that can form both simple "two-component" systems and sophisticated multicomponent systems that integrate stimuli over time and space to generate coordinated and fine-tuned responses. the deltaproteobacterium myxococcus xanthus contains a large repertoire of signaling proteins, many of which regulate its multicellular developmen ... | 2012 | 22661709 |
| complete genome sequence of the fruiting myxobacterium corallococcus coralloides dsm 2259. | corallococcus coralloides, like most other myxobacteria, undergoes a developmental program culminating in the formation of fruiting bodies. c. coralloides fruiting bodies are morphologically distinct from those of other fruiting myxobacteria for which full-length genome sequences are available. the genome sequence of the 10.0-mb c. coralloides genome is presented herein. | 2012 | 22582372 |
| identification and characterization of a putative arginine kinase homolog from myxococcus xanthus required for fruiting body formation and cell differentiation. | arginine kinases catalyze the reversible transfer of a high-energy phosphoryl group from atp to l-arginine to form phosphoarginine, which is used as an energy buffer in insects, crustaceans, and some unicellular organisms. it plays an analogous role to that of phosphocreatine in vertebrates. recently, putative arginine kinases were identified in several bacterial species, including the social gram-negative soil bacterium myxococcus xanthus. it is still unclear what role these proteins play in ba ... | 2012 | 22389486 |
| cell contact-dependent outer membrane exchange in myxobacteria: genetic determinants and mechanism. | biofilms are dense microbial communities. although widely distributed and medically important, how biofilm cells interact with one another is poorly understood. recently, we described a novel process whereby myxobacterial biofilm cells exchange their outer membrane (om) lipoproteins. for the first time we report here the identification of two host proteins, traab, required for transfer. these proteins are predicted to localize in the cell envelope; and traa encodes a distant pa14 lectin-like dom ... | 2012 | 22511878 |
| carf mediates signaling by singlet oxygen, generated via photoexcited protoporphyrin ix, in myxococcus xanthus light-induced carotenogenesis. | blue light triggers carotenogenesis in the nonphototrophic bacterium myxococcus xanthus by inducing inactivation of an anti-σ factor, carr, and the consequent liberation of the cognate extracytoplasmic function (ecf) σ factor, carq. carf, the protein implicated earliest in the response to light, does not resemble any known photoreceptor. it interacts physically with carr and is required for its light-driven inactivation, but the mechanism is unknown. blue-light sensing in m. xanthus has been att ... | 2012 | 22267513 |
| genes encoding cher-tpr fusion proteins are predominantly found in gene clusters encoding chemosensory pathways with alternative cellular functions. | chemosensory pathways correspond to major signal transduction mechanisms and can be classified into the functional families flagellum-mediated taxis, type four pili-mediated taxis or pathways with alternative cellular functions (acf). cher methyltransferases are core enzymes in all of these families. cher proteins fused to tetratricopeptide repeat (tpr) domains have been reported and we present an analysis of this uncharacterized family. we show that cher-tprs are widely distributed in gram-nega ... | 2012 | 23029255 |
| a response regulator interfaces between the frz chemosensory system and the mgla/mglb gtpase/gap module to regulate polarity in myxococcus xanthus. | how cells establish and dynamically change polarity are general questions in cell biology. cells of the rod-shaped bacterium myxococcus xanthus move on surfaces with defined leading and lagging cell poles. occasionally, cells undergo reversals, which correspond to an inversion of the leading-lagging pole polarity axis. reversals are induced by the frz chemosensory system and depend on relocalization of motility proteins between the poles. the ras-like gtpase mgla localizes to and defines the lea ... | 2012 | 23028358 |