| molecular cloning of the gene which encodes beta-n-acetylglucosaminidase from a marine bacterium, alteromonas sp. strain o-7. | the gene encoding the periplasmic beta-n-acetylglucosaminidase (glcnacase b) from a marine alteromonas sp. strain, o-7, was cloned and sequenced. the protein sequence of glcnacase b revealed a highly significant homology with vibrio glcnacase and alpha- and beta-chains of human beta-hexosaminidase. | 1995 | 7574618 |
| cloning, sequence, and expression of a chitinase gene from a marine bacterium, altermonas sp. strain o-7. | the gene encoding an extracellular chitinase from marine alteromonas sp. strain o-7 was cloned in escherichia coli jm109 by using puc18. the chitinase produced was not secreted into the growth medium but accumulated in the periplasmic space. a chitinase-positive clone of e. coli produced two chitinases with different molecular weights from a single chitinase gene. these proteins showed almost the same enzymatic properties as the native chitinase of alteromonas sp. strain o-7. the n-terminal sequ ... | 1993 | 8416892 |
| cloning and expression of a gene encoding a bacterial enzyme for decontamination of organophosphorus nerve agents and nucleotide sequence of the enzyme. | organophosphorus acid (opa) anhydrolase enzymes have been found in a wide variety of prokaryotic and eukaryotic organisms. interest in these enzymes has been prompted by their ability to catalyze the hydrolysis of toxic organophosphorus cholinesterase-inhibiting compounds, including pesticides and chemical nerve agents. the natural substrates for these enzymes are unknown. the gene (opaa) which encodes an opa anhydrolase (opaa-2) was isolated from an alteromonas sp. strain jd6.5 ecori-lambda zap ... | 1996 | 8633861 |
| identification and characterization of the three chitin-binding domains within the multidomain chitinase chi92 from aeromonas hydrophila jp101. | the gene (chi92) encoding the extracellular chitinase of aeromonas hydrophila jp101 has been cloned and expressed in escherichia coli. the mature form of chi92 is an 842-amino-acid (89.830-kda) modular enzyme comprised of a family 18 catalytic domain, an unknown-function region (the a region), and three chitin-binding domains (chbds; chi92-n, chbd(ci), and chbd(cii)). the c-terminally repeated chbds, chbd(ci) and chbd(cii), were grouped into family v of cellulose-binding domains on the basis of ... | 2001 | 11679332 |
| pseudomonas aeruginosa c5-mannuronan epimerase: steady-state kinetics and characterization of the product. | alginate is a major constituent of mature biofilms produced by pseudomonas aeruginosa. the penultimate step in the biosynthesis of alginate is the conversion of some beta-d-mannuronate residues in the polymeric substrate polymannuronan to alpha-l-guluronate residues in a reaction catalyzed by c5-mannuronan epimerase. specificity studies conducted with size-fractionated oligomannuronates revealed that the minimal substrate contained nine monosaccharide residues. the maximum velocity of the reacti ... | 2006 | 16401084 |
| family 18 chitolectins: comparison of mgp40 and humgp39. | glycosidase and lectins both bind sugars, but only the glycosidases have catalytic activity. the glycosidases occur among over 100 evolved protein families and family 18 is one of the two chitinases (ec 3, 2.1.14) families. interestingly, lectins are also in this evolutionary group of family 18 glycosidase proteins. the proteins belonging to the enzymatically inactive class are referred to as chitolectins and have a binding site that is highly similar to the catalytic family 18 enzymes. we prese ... | 2007 | 17543889 |
| the effects of the surface-exposed residues on the binding and hydrolytic activities of vibrio carchariae chitinase a. | vibrio carchariae chitinase a (ec3.2.1.14) is a family-18 glycosyl hydrolase and comprises three distinct structural domains: i) the amino terminal chitin binding domain (chbd); ii) the (alpha/beta)8 tim barrel catalytic domain (catd); and iii) the alpha + beta insertion domain. the predicted tertiary structure of v. carchariae chitinase a has located the residues ser33 & trp70 at the end of chbd and trp231 & tyr245 at the exterior of the catalytic cleft. these residues are surface-exposed and p ... | 2008 | 18205958 |
| structural and mutational characterization of the catalytic a-module of the mannuronan c-5-epimerase alge4 from azotobacter vinelandii. | alginate is a family of linear copolymers of (1-->4)-linked beta-d-mannuronic acid and its c-5 epimer alpha-l-guluronic acid. the polymer is first produced as polymannuronic acid and the guluronic acid residues are then introduced at the polymer level by mannuronan c-5-epimerases. the structure of the catalytic a-module of the azotobacter vinelandii mannuronan c-5-epimerase alge4 has been determined by x-ray crystallography at 2.1-a resolution. alge4a folds into a right-handed parallel beta-heli ... | 2008 | 18574239 |
| analysis of the pseudoalteromonas tunicata genome reveals properties of a surface-associated life style in the marine environment. | colonisation of sessile eukaryotic host surfaces (e.g. invertebrates and seaweeds) by bacteria is common in the marine environment and is expected to create significant inter-species competition and other interactions. the bacterium pseudoalteromonas tunicata is a successful competitor on marine surfaces owing primarily to its ability to produce a number of inhibitory molecules. as such p. tunicata has become a model organism for the studies into processes of surface colonisation and eukaryotic ... | 2008 | 18813346 |
| the genome sequence of the fish pathogen aliivibrio salmonicida strain lfi1238 shows extensive evidence of gene decay. | the fish pathogen aliivibrio salmonicida is the causative agent of cold-water vibriosis in marine aquaculture. the gram-negative bacterium causes tissue degradation, hemolysis and sepsis in vivo. | 2008 | 19099551 |
| sulfide, microcystin, and the etiology of black band disease. | black band disease (bbd) consists of a cyanobacterial-dominated, sulfide-rich microbial mat that migrates across coral colonies, degrading coral tissue. the mat contains diverse bacteria that include photoautotrophs (cyanobacteria), sulfate-reducers, sulfide-oxidizers, and organoheterotrophs. bbd sulfate-reducers contribute to bbd pathobiology by production of sulfide, which causes coral tissue lysis and death, and the cyanotoxin microcystin is produced by bbd cyanobacteria. here we used a model ... | 2009 | 20095243 |
| in vitro release of organophosphorus acid anhydrolase from functionalized mesoporous silica against nerve agents. | we report here that under different physiological conditions, biomolecular drugs can be stockpiled in a nanoporous support and afterward can be instantly released when needed for acute responses, and the biomolecular drug molecules can also be gradually released from the nanoporous support over a long time for a complete recovery. organophosphorus acid anhydrolase (opaa) was spontaneously and largely entrapped in functionalized mesoporous silica (fms) due to the dominant electrostatic interactio ... | 2011 | 22019765 |
| in vitro release of organophosphorus acid anhydrolase from functionalized mesoporous silica against nerve agents. | we report here that under different physiological conditions, biomolecular drugs can be stockpiled in a nanoporous support and afterward can be instantly released when needed for acute responses, and the biomolecular drug molecules can also be gradually released from the nanoporous support over a long time for a complete recovery. organophosphorus acid anhydrolase (opaa) was spontaneously and largely entrapped in functionalized mesoporous silica (fms) due to the dominant electrostatic interactio ... | 2011 | 22019765 |
| prokaryote-derived protein inhibitors of peptidases: a sketchy occurrence and mostly unknown function. | in metazoan organisms protein inhibitors of peptidases are important factors essential for regulation of proteolytic activity. in vertebrates genes encoding peptidase inhibitors constitute up to 1% of genes reflecting a need for tight and specific control of proteolysis especially in extracellular body fluids. in stark contrast unicellular organisms, both prokaryotic and eukaryotic consistently contain only few, if any, genes coding for putative peptidase inhibitors. this may seem perplexing in ... | 2010 | 20558234 |
| diguanylate cyclase nicd-based signalling mechanism of nutrient-induced dispersion by pseudomonas aeruginosa. | dispersion enables the transition from the biofilm to the planktonic growth state in response to various cues. while several pseudomonas aeruginosa proteins, including bdla and the c-di-gmp phosphodiesterases dipa, rbda, and nbda, have been shown to be required for dispersion to occur, little is known about dispersion cue sensing and the signalling translating these cues into the modulation c-di-gmp levels to enable dispersion. using glutamate-induced dispersion as a model, we report that disper ... | 2014 | 25243483 |
| the renaissance of bacillosamine and its derivatives: pathway characterization and implications in pathogenicity. | prokaryote-specific sugars, including n,n'-diacetylbacillosamine (dinacbac) and pseudaminic acid, have experienced a renaissance in the past decade because of their discovery in glycans related to microbial pathogenicity. dinacbac is found at the reducing end of oligosaccharides of n- and o-linked bacterial protein glycosylation pathways of gram-negative pathogens, including campylobacter jejuni and neisseria gonorrhoeae. further derivatization of dinacbac results in the nonulosonic acid known a ... | 2014 | 24383882 |
| catalytic bioscavengers against toxic esters, an alternative approach for prophylaxis and treatments of poisonings. | bioscavengers are biopharmaceuticals that specifically react with toxicants. thus, enzymes reacting with poisonous esters can be used as bioscavengers for neutralization of toxic molecules before they reach physiological targets. parenteral administration of bioscavengers is, therefore, intended for prophylaxis or pre-treatments, emergency and post-exposure treatments of intoxications. these enzymes can also be used for application on skin, mucosa and wounds as active components of topical skin ... | 2009 | 22649587 |
| a survey of orphan enzyme activities. | using computational database searches, we have demonstrated previously that no gene sequences could be found for at least 36% of enzyme activities that have been assigned an enzyme commission number. here we present a follow-up literature-based survey involving a statistically significant sample of such "orphan" activities. the survey was intended to determine whether sequences for these enzyme activities are truly unknown, or whether these sequences are absent from the public sequence databases ... | 2007 | 17623104 |
| flanking signal and mature peptide residues influence signal peptide cleavage. | signal peptides (sps) mediate the targeting of secretory precursor proteins to the correct subcellular compartments in prokaryotes and eukaryotes. identifying these transient peptides is crucial to the medical, food and beverage and biotechnology industries yet our understanding of these peptides remains limited. this paper examines the most common type of signal peptides cleavable by the endoprotease signal peptidase i (spase i), and the residues flanking the cleavage sites of three groups of s ... | 2008 | 19091014 |
| embryo protection in contemporary immunology: why bacteria matter. | early embryos of many vertebrates and invertebrates develop outside the mother and are exposed to a myriad of potential microbial colonizers. here we discuss how these embryos are protected from microbial attacks and how they might control and shape their microbiota. in essence we delineate a new role for antimicrobial peptides both in selecting particular bacterial partners during early development and in being important components of a "be prepared" strategy providing transgenerational protect ... | 2011 | 21966549 |
| transcriptional activation of c3 and hsp70 as part of the immune response of acropora millepora to bacterial challenges. | the impact of disease outbreaks on coral physiology represents an increasing concern for the fitness and resilience of reef ecosystems. predicting the tolerance of corals to disease relies on an understanding of the coral immune response to pathogenic interactions. this study explored the transcriptional response of two putative immune genes (c3 and c-type lectin) and one stress response gene (hsp70) in the reef building coral, acropora millepora challenged for 48 hours with bacterial strains, v ... | 2013 | 23861754 |
| structural basis of substrate selectivity of e. coli prolidase. | prolidases, metalloproteases that catalyze the cleavage of xaa-pro dipeptides, are conserved enzymes found in prokaryotes and eukaryotes. in humans, prolidase is crucial for the recycling of collagen. to further characterize the essential elements of this enzyme, we utilized the escherichia coli prolidase, pepq, which shares striking similarity with eukaryotic prolidases. through structural and bioinformatic insights, we have extended previous characterizations of the prolidase active site, unco ... | 2014 | 25354344 |
| combination of uniform design with artificial neural network coupling genetic algorithm: an effective way to obtain high yield of biomass and algicidal compound of a novel habs control actinomycete. | controlling harmful algae blooms (habs) using microbial algicides is cheap, efficient and environmental-friendly. however, obtaining high yield of algicidal microbes to meet the need of field test is still a big challenge since qualitative and quantitative analysis of algicidal compounds is difficult. in this study, we developed a protocol to increase the yield of both biomass and algicidal compound present in a novel algicidal actinomycete streptomyces alboflavus rps, which kills phaeocystis gl ... | 2014 | 24886410 |
| microbial communication leading to the activation of silent fungal secondary metabolite gene clusters. | microorganisms form diverse multispecies communities in various ecosystems. the high abundance of fungal and bacterial species in these consortia results in specific communication between the microorganisms. a key role in this communication is played by secondary metabolites (sms), which are also called natural products. recently, it was shown that interspecies "talk" between microorganisms represents a physiological trigger to activate silent gene clusters leading to the formation of novel sms ... | 2015 | 25941517 |