molecular cloning and functional characterization of a unique multipotent polyphenol oxidase from marinomonas mediterranea.marinomonas mediterranea is a recently isolated melanogenic marine bacterium containing laccase and tyrosinase activities. these activities are due to the expression of two polyphenol oxidases (ppos), a blue multicopper laccase and an sds-activated tyrosinase. the gene encoding the first one, herein denominated m. mediterranea ppoa, has been isolated by transposon mutagenesis, cloned and expressed in escherichia coli. its predicted amino acid sequence shows the existence of a signal peptide and ...200111343796
dimethoxyphenol oxidase activity of different microbial blue multicopper proteins.2,6-dimethoxyphenol is a versatile substrate for pyricularia oryzae laccase, ppoa from marinomonas mediterranea, phenoxazinone synthase from streptomyces antibioticus and mammalian ceruloplasmin. in addition, in cellular extracts of microorganisms expressing other blue multicopper proteins with no enzymatic activity previously described, such as escherichia coli (copper resistance cueo), pseudomonas syringae and xanthomonas campestris (copper resistance copa), bacillus subtilis (sporulation prot ...200111682198
regulation of polyphenol oxidase activities and melanin synthesis in marinomonas mediterranea: identification of ppos, a gene encoding a sensor histidine kinase.marinomonas mediterranea is a melanogenic marine bacterium that expresses two different polyphenol oxidases. one of them is a multipotent laccase able to oxidize a wide range of substrates. the second enzyme is an sds-activated tyrosinase. using transposon mutagenesis, a mutant affected in the regulation of both polyphenol oxidase activities and melanogenesis has been isolated. the sequencing of the gene disrupted by the mini-tn10 transposon in this mutant indicates that it encodes a hybrid sens ...200212177339
purification and partial characterization of marinocine, a new broad-spectrum antibacterial protein produced by marinomonas mediterranea.this work describes the purification and partial characterization of a novel antibacterial compound, here named marinocine, produced by marinomonas mediterranea, a melanogenic marine bacterium with rich secondary metabolism. the antibacterial compound is a protein detected in the medium at death phase of growth. it has been purified to apparent homogeneity from the supernatants of cultures by means of ethanol precipitation followed by column chromatographies on deae-sephadex and sephacryl hr-200 ...200415652194
marinomonas pontica sp. nov., isolated from the black sea.a gram-negative, polarly flagellated bacterium was isolated from a sea-water sample collected from the karadag natural reserve of the eastern crimea and characterized to clarify its taxonomic position. 16s rrna gene sequence-based phylogenetic analysis of this novel organism revealed marinomonas vaga, marinomonas communis, marinomonas mediterranea, marinomonas primoryensis and 'marinomonas protea' as its closest relatives (similarity 95-97 %). the g+c content of the dna was 46.5 mol%. the organi ...200515653887
hydrogen peroxide linked to lysine oxidase activity facilitates biofilm differentiation and dispersal in several gram-negative bacteria.the marine bacterium pseudoalteromonas tunicata produces an antibacterial and autolytic protein, alpp, which causes death of a subpopulation of cells during biofilm formation and mediates differentiation, dispersal, and phenotypic variation among dispersal cells. the alpp homologue (loda) in the marine bacterium marinomonas mediterranea was recently identified as a lysine oxidase which mediates cell death through the production of hydrogen peroxide. here we show that alpp in p. tunicata also act ...200818502869
taxonomic study of marinomonas strains isolated from the seagrass posidonia oceanica, with descriptions of marinomonas balearica sp. nov. and marinomonas pollencensis sp. nov.novel aerobic, gram-negative bacteria with dna g+c contents below 50 mol% were isolated from the culturable microbiota associated with the mediterranean seagrass posidonia oceanica. 16s rrna gene sequence analyses revealed that they belong to the genus marinomonas. strain ivia-po-186 is a strain of the species marinomonas mediterranea, showing 99.77 % 16s rrna gene sequence similarity with the type strain, mmb-1(t), and sharing all phenotypic characteristics studied. this is the first descriptio ...201019648336
both genes in the marinomonas mediterranea lodab operon are required for the expression of the antimicrobial protein lysine oxidase.the melanogenic marine bacterium marinomonas mediterranea synthesizes a novel antimicrobial protein (loda) with lysine-epsilon oxidase activity (ec homologues to loda have been detected in several gram-negative bacteria, where they are involved in biofilm development. adjacent to loda is located a second gene, lodb, of unknown function. this genomic organization is maintained in all the microorganisms containing homologues to these genes. in this work we show that loda and lodb consti ...201020025674
regulation of the marinomonas mediterranea antimicrobial protein lysine oxidase by l-lysine and the sensor histidine kinase ppos.some gram-negative bacteria express a novel enzyme with lysine-epsilon-oxidase (lod) activity (ec the oxidation of l-lys generates, among other products, hydrogen peroxide, which confers antimicrobial properties to this kind of enzyme and has been shown to be involved in cell death during biofilm development and differentiation. in addition to lod, the melanogenic marine bacterium marinomonas mediterranea, which forms part of the microbiota of the marine plant posidonia oceanica, expr ...201020656878
a novel laccase with urate oxidation activity from lysobacter sp. t-15.a unique urate-oxidizing enzyme was identified in a bacterium, strain t-15. based on its phylogenetic, physiological and biochemical properties, strain t-15 was deemed to be a novel species within the genus lysobacter. the enzyme expressed in lysobacter sp. t-15 was composed of 592 amino acids and contained four consensus copper-binding sites, and the recombinant enzyme was, at least in this study, speculated to have three cu ions per subunit. the primary structure of the enzyme was 33% identica ...201020675295
distribution in microbial genomes of genes similar to loda and goxa which encode a novel family of quinoproteins with amino acid oxidase activity.l-amino acid oxidases (laos) have been generally described as flavoproteins that oxidize amino acids releasing the corresponding ketoacid, ammonium and hydrogen peroxide. the generation of hydrogen peroxide gives to these enzymes antimicrobial characteristics. they are involved in processes such as biofilm development and microbial competition. laos are of great biotechnological interest in different applications such as the design of biosensors, biotransformations and biomedicine. the marine ba ...201525886995
complete genome sequence of the melanogenic marine bacterium marinomonas mediterranea type strain (mmb-1(t)).marinomonas mediterranea mmb-1(t) solano & sanchez-amat 1999 belongs to the family oceanospirillaceae within the phylum proteobacteria. this species is of interest because it is the only species described in the genus marinomonas to date that can synthesize melanin pigments, which is mediated by the activity of a tyrosinase. m. mediterranea expresses other oxidases of biotechnological interest, such as a multicopper oxidase with laccase activity and a novel l-lysine-epsilon-oxidase. the 4,684,31 ...201222675599
identification in marinomonas mediterranea of a novel quinoprotein with glycine oxidase activity.a novel enzyme with lysine-epsilon oxidase activity was previously described in the marine bacterium marinomonas mediterranea. this enzyme differs from other l-amino acid oxidases in not being a flavoprotein but containing a quinone cofactor. it is encoded by an operon with two genes loda and lodb. the first one codes for the oxidase, while the second one encodes a protein required for the expression of the former. genome sequencing of m. mediterranea has revealed that it contains two additional ...201323873697
purification and characterization of antibacterial compounds of pseudoalteromonas flavipulchra jg1.pseudoalteromonas flavipulchra jg1 produces a protein pfap and a range of small molecular compounds with inhibitory activities against vibrio anguillarum. the pfap protein was purified from the extracellular products of jg1 by electroelution, and antibacterial activity was observed by the in-gel antibacterial assay. the complete amino acid sequence (694 aa) of pfap was determined by de novo peptide sequencing and subsequently aligning with the proteome sequence of strain jg1. the calculated mole ...201122194352
determination of plasma and serum l-lysine using l-lysine epsilon-oxidase from marinomonas mediterranea nbrc 103028(t).this article describes a successful application of l-lysine epsilon-oxidase (ec for l-lysine determination. l-lysine epsilon-oxidase was isolated from culture supernatant of marinomonas mediterranea nbrc 103028(t) and was used for l-lysine determination. comparison of the characteristics of l-lysine epsilon-oxidase with l-lysine alpha-oxidase, a commercial enzyme used for l-lysine determination, suggests that the use of l-lysine epsilon-oxidase would be more valuable for the determinat ...201020599635
finding new enzymes from bacterial physiology: a successful approach illustrated by the detection of novel oxidases in marinomonas mediterranea.the identification and study of marine microorganisms with unique physiological traits can be a very powerful tool discovering novel enzymes of possible biotechnological interest. this approach can complement the enormous amount of data concerning gene diversity in marine environments offered by metagenomic analysis, and can help to place the activities associated with those sequences in the context of microbial cellular metabolism and physiology. accordingly, the detection and isolation of micr ...201020411113
involvement of a novel copper chaperone in tyrosinase activity and melanin synthesis in marinomonas mediterranea.tyrosinase activity and melanin synthesis in the marine bacterium marinomonas mediterranea in media with very low copper concentrations are dependent on the presence of a protein (ppob2) that functions as a chaperone to deliver copper to tyrosinase (ppob1). under these conditions, mutants in ppob2 (such as strain t105) produce ppob1 as an apoenzyme that can be reconstituted to the active holoenzyme by the addition of cupric ions to cell extracts. to study ppob2 functionality, a system was develo ...200717600068
a novel type of lysine oxidase: l-lysine-epsilon-oxidase.the melanogenic marine bacterium m. mediterranea synthesizes marinocine, a protein with antibacterial activity. we cloned the gene coding for this protein and named it loda [p. lucas-elío, p. hernández, a. sanchez-amat, f. solano, purification and partial characterization of marinocine, a new broad-spectrum antibacterial protein produced by marinomonas mediterranea. biochim. biophys. acta 1721 (2005) 193-203; p. lucas-elío, d. gómez, f. solano, a. sanchez-amat, the antimicrobial activity of mari ...200617030025
influence of lipopolysaccharides and lipids a from some marine bacteria on spontaneous and escherichia coli lps-induced tnf-alpha release from peripheral human blood cells.some endotoxic properties of lipopolysaccharides (lps) and lipids a (la) from the marine bacteria marinomonas communis atcc 27118(t), marinomonas mediterranea atcc 700492(t), and chryseobacterium indoltheticum cip 103168(t) were studied. the preparations tested were shown to have high 50% lethal doses (4 microg per mouse for lps from m. mediterranea and more than 12 microg per mouse for two other lps and la from c. indoltheticum) and were moderate (371 +/- 37 pg/ml at 10 microg/ml of c. indolthe ...200616903830
the antimicrobial activity of marinocine, synthesized by marinomonas mediterranea, is due to hydrogen peroxide generated by its lysine oxidase activity.marinocine is a broad-spectrum antibacterial protein synthesized by the melanogenic marine bacterium marinomonas mediterranea. this work describes the basis for the antibacterial activity of marinocine and the identification of the gene coding for this protein. the antibacterial activity is inhibited under anaerobic conditions and by the presence of catalase under aerobic conditions. marinocine is active only in culture media containing l-lysine. in the presence of this amino acid, marinocine ge ...200616547036
alkali and halide-resistant catalysis by the multipotent oxidase from marinomonas mediterranea.the incorporation of fungal laccases into novel applications has been delayed mainly due to their intrinsic sensitivity towards halides and alkaline conditions. in order to explore new sources of enzymes we evaluated the multipotent polyphenol oxidase ppo1 from the marine bacterium marinomonas mediterranea. here we report that, in contrast to its fungal counterparts, ppo1 remained functional above neutral ph presenting high specificity for phenolic compounds, in particular for methoxyl-substitut ...200515831249
identification of an operon involved in tyrosinase activity and melanin synthesis in marinomonas mediterranea.the genomic region of marinomonas mediterranea containing the genes required for tyrosinase activity and melanin synthesis has been cloned by marker rescue using the transposon-generated, amelanogenic strain t105. five orfs, two incomplete and three complete, have been sequenced in the genomic region where the transposon was inserted. rt-pcr analysis indicates that orf 3, coding for tyrosinase, and orf4, coding for a protein of 250 amino acids, are in the same transcriptional unit, constituting ...200415527977
marinomonas mediterranea is a lysogenic bacterium that synthesizes r-bodies.the melanogenic marine bacterium marinomonas mediterranea synthesizes r-bodies as revealed by transmission electron microscopy. these structures were previously described in some obligate symbionts of paramecia and some free-living bacteria, none of which was isolated from sea water. in other micro-organisms, the synthesis of r-bodies has been related to extrachromosomal elements. accordingly, m. mediterranea induction by mitomycin c or uv radiation resulted in the production of defective phages ...200312949192
cloning and molecular characterization of a sds-activated tyrosinase from marinomonas mediterranea.the sequence of the tyrosinase gene cloned from marinomonas mediterranea is reported. it is the second tyrosinase cloned from a gram negative bacterium. its size is higher than that of gram positive tyrosinases from streptomyces, and more similar to the eukaryotic enzymes. its sequence shares the features of copper-binding sites found in all tyrosinases. based in the comparison of tyrosinases from all types of organisms, an extension of the characteristic signatures existing at prosite is propos ...200211936267
marinomonas mediterranea mmb-1 transposon mutagenesis: isolation of a multipotent polyphenol oxidase mutant.marinomonas mediterranea is a melanogenic marine bacterium expressing a multifunctional polyphenol oxidase (ppo) able to oxidize substrates characteristic for laccases and tyrosinases, as well as produce a classical tyrosinase. a new and quick method has been developed for screening laccase activity in culture plates to detect mutants differentially affected in this ppo activity. transposon mutagenesis has been applied for the first time to m. mediterranea by using different minitransposons load ...200010850991
location and catalytic characteristics of a multipotent bacterial polyphenol oxidase.the melanogenic marine bacterium marinomonas mediterranea contains a multipotent polyphenol oxidase (ppo) able to oxidize substrates characteristic for tyrosinase and laccase. thus, this enzyme shows tyrosine hydroxylase activity and it catalyzes the oxidation of a wide variety of o-diphenol as well as o-methoxy-activated phenols. the study of its sensitivity to different inhibitors also revealed intermediate features between laccase and tyrosinase. it is similar to tyrosinases in its sensitivit ...199910541043
studies on the phylogenetic relationships of melanogenic marine bacteria: proposal of marinomonas mediterranea sp. nov.the polyphenol oxidase (ppo) activities of the marine melanogenic strains mmb-1t and 2-40 were compared. both contained a multifunctional ppo able to oxidize a wide range of substrates. in spite of this similarity, phylogenetic studies based on 16s rrna sequences showed that these strains are not closely related. strain 2-40 is not related to any previously described genus. on the basis of these studies and morphological and physiological characteristics, it is proposed that strain mmb-1t (= cec ...199910425786
investigating antimicrobial activity in rheinheimera sp. due to hydrogen peroxide generated by l-lysine oxidase activity.a greenish yellow pigmented bacterial strain, designated gr5, was recently isolated from a freshwater culture pond for a soft-shell turtle. phylogenetic analyses based on 16s rrna gene sequences indicate that strain gr5 belongs to the genus rheinheimera and its only closest neighbor is the type strain of rheinheimera texasensis (98.2%). based on the antibiogram assay, strain gr5 possesses a broad spectrum of antimicrobial activity including gram-positive and gram-negative bacteria, yeast, algae, ...201025919624
x-ray crystallographic evidence for the presence of the cysteine tryptophylquinone cofactor in l-lysine ε-oxidase from marinomonas mediterranea.we have determined the x-ray crystal structure of l-lysine ε-oxidase from marinomonas mediterranea in its native and l-lysine-complex forms at 1.94- and 1.99-å resolution, respectively. in the native enzyme, electron densities clearly indicate the presence of cysteine tryptophylquinone (ctq) previously identified in quinohemoprotein amine dehydrogenase. in the l-lysine-complex, an electron density corresponding to the bound l-lysine shows that its ε-amino group is attached to the c6 carbonyl gro ...201323908359
characterization of recombinant biosynthetic precursors of the cysteine tryptophylquinone cofactors of l-lysine-epsilon-oxidase and glycine oxidase from marinomonas mediterranea.the lysine-ε-oxidase, loda, and glycine oxidase, goxa, from marinomonas mediteranea each possesses a cysteine tryptophylquinone (ctq) cofactor. this cofactor is derived from posttranslational modifications which are covalent crosslinking of tryptophan and cysteine residues and incorporation of two oxygen atoms into the indole ring of trp. in this manuscript, it is shown that the recombinant synthesis of loda and goxa containing a fully synthesized ctq cofactor requires coexpression of a partner ...201525542375
direct crispr spacer acquisition from rna by a natural reverse transcriptase-cas1 fusion protein.crispr systems mediate adaptive immunity in diverse prokaryotes. crispr-associated cas1 and cas2 proteins have been shown to enable adaptation to new threats in type i and ii crispr systems by the acquisition of short segments of dna (spacers) from invasive elements. in several type iii crispr systems, cas1 is naturally fused to a reverse transcriptase (rt). in the marine bacterium marinomonas mediterranea (mmb-1), we showed that a rt-cas1 fusion protein enables the acquisition of rna spacers in ...201626917774
lodb is required for the recombinant synthesis of the quinoprotein l-lysine-ε-oxidase from marinomonas mediterranea.marinomonas mediterranea is a marine gamma-proteobacterium that synthesizes loda, a novel l-lysine-ε-oxidase (e.c. this enzyme oxidizes l-lysine generating 2-aminoadipate 6-semialdehyde, ammonium, and hydrogen peroxide. unlike other l-amino acid oxidases, loda is not a flavoprotein but contains a quinone cofactor. loda is encoded by an operon with two genes, loda and lodb. in the native system, lodb is required for the synthesis of a functional loda. in this study, we report the recom ...201423955504
different recombinant forms of polyphenol oxidase a, a laccase from marinomonas mediterranea.polyphenol oxidase from the marine bacterium marinomonas mediterranea (mmppoa) is a membrane-bound, blue, multi-copper laccase of 695 residues. it possesses peculiar properties that distinguish it from known laccases, such as a broad substrate specificity (common to tyrosinases) and a high redox potential. in order to push the biotechnological application of this laccase, the full-length enzyme was overexpressed in escherichia coli cells with and without a c-terminal his-tag. the previous form, ...201627050199
distribution in different organisms of amino acid oxidases with fad or a quinone as cofactor and their role as antimicrobial proteins in marine bacteria.amino acid oxidases (aaos) catalyze the oxidative deamination of amino acids releasing ammonium and hydrogen peroxide. several kinds of these enzymes have been reported. depending on the amino acid isomer used as a substrate, it is possible to differentiate between l-amino acid oxidases and d-amino acid oxidases. both use fad as cofactor and oxidize the amino acid in the alpha position releasing the corresponding keto acid. recently, a novel class of aaos has been described that does not contain ...201526694422
Displaying items 1 - 34 of 34