Abstract Background Enterobacter sakazakii is an opportunistic pathogen that can cause infections such as necrotizing enterocolitis, bacteraemia, meningitis and brain abscess/lesions. When the species was defined in 1980, 15 biogroups were described it suggested these could represent multiple species. In this study taxonomic relationship of strains E. further investigated. Results Strains identified divided into separate groups on basis f-AFLP fingerprints, ribopatterns full-length 16S rRNA...

The production of pediocin PA-1, a small heat-stable bacteriocin, is associated with the presence 9.4-kbp plasmid pSRQ11 in Pediococcus acidilactici PAC1.0. It was shown by subcloning Escherichia coli cloning vectors that PA-1 produced and, most probably, secreted E. cells. Deletion analysis showed 5.6-kbp SalI-EcoRI fragment derived from required for production. Nucleotide sequence this indicated four clustered open reading frames (pedA, pedB, pedC, and pedD). pedA gene encodes...

Lactococcus lactis strain NIZO B40 produces an extracellular phosphopolysaccharide containing galactose, glucose, and rhamnose. A 40 kb plasmid encoding exopolysaccharide production was isolated through conjugal transfer of total DNA from to the plasmid‐free L. model MG1614 subsequent curing. 12 region 14 genes with order epsRXABCDEFGHIJKL identified downstream iso‐IS 982 element. The predicted gene products epsABCDEFGHIJK show sequence homologies involved in exopolysaccharide, capsular...

The bacteriocin pediocin PA‐1 operon of Pediococcus acidilactici PAC1.0 encompasses four genes: pedA, pedB, pedC and pedD . Transcription the results in formation two overlapping transcripts, probably originating from a single promoter upstream pedA major transcript comprises pedB , while minor all these genes By deletion analysis overexpression pentosaceus we demonstrate that this gene encodes immunity protein. Prepediocin is active Escherichia coli when was expressed concomitantly with...

The plant-growth-stimulating Pseudomonas putida WCS358 was mutagenized with transposon Tn5. resulting mutant colony bank screened for mutants defective in the biosynthesis of fluorescent siderophore. A total 28 mutants, divided into six different classes, were isolated that nonfluorescent or iron acquisition both. These types together probable overall structure siderophore, i.e., a small peptide chain attached to fluorescing group, suggest biosynthetic pathway which synthesis group is...

A taxonomic reclassification of the neonatal pathogen Enterobacter sakazakii to consist five species within a new genus, "Cronobacter," has recently been proposed. The correct identification these organisms is important clinicians. Therefore, using 312 Enterobacteriaceae, including 210 "Cronobacter" strains, reliabilities biochemical and genetic confirmation tests were investigated. All isolates positive dnaG gluA PCR protocols, all expressed alpha-glucosidase activity. ID32E v3.0 identified...

Summary The initial step in the uptake of iron via ferric pseudobactin by plant‐growth‐promoting Pseudomonas putida strain WCS358 is binding to a specific outer‐membrane protein. nucleotide sequence pupA structural gene, which codes for receptor, was determined. It contains single open reading frame potentially encodes polypeptide 819 amino acids, including putative N ‐terminal signal 47 acids. Significant homology, concentrated four boxes, found with TonB‐dependent receptor proteins...

Transcriptional gene fusions with the Escherichia coli beta-glucuronidase (gusA) were used to study medium- and growth-dependent expression of divergently transcribed genes involved in proteinase production (prtP prtM) Lactococcus lactis SK11. The results show that both prtP prtM are controlled at transcriptional level by peptide content medium and, a lesser extent, growth rate. A more than 10-fold regulation activity was observed for promoters batch continuous cultures. high whey permeate...

ABSTRACT We used homologous and heterologous expression of the glycosyltransferase genes Lactococcus lactis NIZO B40 eps gene cluster to determine activity substrate specificities encoded enzymes established order assembly trisaccharide backbone exopolysaccharide repeating unit. EpsD links glucose-1-phosphate from UDP-glucose a lipid carrier, EpsE EpsF link glucose lipid-linked glucose, EpsG galactose UDP-galactose cellobiose. Furthermore, EpsJ appeared be involved in EPS biosynthesis as...

The enzymatic degradation of amino acids in cheese is believed to generate aroma compounds and therefore be essential for flavor development. Cystathionine beta-lyase (CBL) can convert cystathionine homocysteine but also able catalyze an alpha, gamma elimination. With methionine as a substrate, it produces volatile sulfur which are important formation Gouda cheese. metC gene, encodes CBL, was cloned from the Lactococcus lactis model strain MG1363 B78, isolated starter culture known have high...

The biosynthetic pathway for the synthesis of compatible solute alpha-mannosylglycerate in hyperthermophilic archaeon Pyrococcus horikoshii is proposed based on activities purified recombinant mannosyl-3-phosphoglycerate (MPG) synthase and phosphatase. former activity was from cell extracts, N-terminal sequence used to identify encoding gene completely sequenced P. genome. This gene, designated PH0927, a immediately downstream (PH0926) were cloned overexpressed Escherichia coli. product...

The biosynthetic reaction scheme for the compatible solute mannosylglycerate in Rhodothermus marinus is proposed based on measurements of relevant enzymatic activities cell-free extracts and vivo (13)C labeling experiments. synthesis proceeded via two alternative pathways; one them, GDP mannose was condensed with D-glycerate to produce a single catalyzed by synthase, other pathway, mannosyl-3-phosphoglycerate synthase conversion D-3-phosphoglycerate into phosphorylated intermediate, which...

A simple two-step procedure was developed to obtain pure enterocin 4, a bacteriocin produced by Enterococcus faecalis INIA 4. Chemical and genetic characterization revealed that the primary structure of 4 is identical peptide antibiotic AS-48 from S-48. In contrast reported inhibitory spectrum AS-48, displayed no activity against gram-negative bacteria.

Two different Lactococcus lactis host strains, L. subsp. MG1363 and cremoris SK1128, both containing plasmid pNZ521, which encodes the extracellular serine proteinase (PrtP) from strain SK110, were used to study medium growth-rate-dependent activity of three enzymes involved in proteolytic system lactococci. The levels PrtP intracellular aminopeptidase PepN X-prolyl-dipeptidyl PepXP studied during batch continuous cultivation. In level was regulated by peptide content medium. highest found...

Lactic acid bacteria have an essential role in the majority of food fermentations, and many different strains are used as starter cultures for meat, dairy, vegetable bakery products. long been known to produce antimicrobial proteins called bacteriocins. There two major classes bacteriocins produced by lactic bacteria, those (e.g. lactacin B F, lactocin 27) that cidal a narrow range target organisms, usually closely related producer nisin, pediocin A, PA‐1) inhibit broad spectrum...

Rhodothermus marinus responds to fluctuations in the growth temperature and/or salinity by accumulating mannosylglycerate (MG). Two alternative pathways for synthesis of MG have been identified this bacterium: a single-step pathway and two-step pathway. In work, genetic biochemical characterization was carried out with goal understanding function two their regulatory mechanisms. Mannosyl-3-phosphoglycerate synthase (MPGS) purified from R. marinus. Sequence information led isolation...

Strains of Thermus thermophilus accumulate primarily trehalose and smaller amounts mannosylglycerate in response to salt stress yeast extract-containing media (O. C. Nunes, M. Manaia, S. da Costa, H. Santos, Appl. Environ. Microbiol. 61:2351-2357, 1995). A 2.4-kbp DNA fragment from T. strain RQ-1 carrying otsA (encoding trehalose-phosphate synthase [TPS]), otsB phosphatase [TPP]), a short sequence the 5' end treS (trehalose [TreS]) was cloned gene library. The sequences three genes...

In iron-limited environments plant-growth-stimulating Pseudomonas putida WCS358 produces a yellow-green fluorescent siderophore called pseudobactin 358. Ferric 358 is efficiently taken up by cells of but not another rhizophere-colonizing strain, fluorescens WCS374. A gene bank containing partial Sau3A DNA fragments from was constructed in derivative the broad-host-range cosmid pLAFR1. By mobilization this to strain WCS374 clone, pMR, which made competent for utilization identified....

In iron-limited environments, the plant-growth-stimulating Pseudomonas putida WCS358 produces a yellow-green fluorescent siderophore called pseudobactin 358. The transcriptional organization and iron-regulated expression of major gene cluster involved in biosynthesis transport 358 were analyzed detail. comprises region with minimum length 33.5 kilobases contains at least five units, which some are relatively large. directions transcription four units determined by RNA-RNA hybridization...