Two Genes Encoding Serine Protease Homologues in Serratia marcescens and Characterization of Their Products in Escherichia coli

ABSTRACTThe aim of the study was to identify the plasmid-encoded factors contributing to the emergence and spread of epidemic IncI1-Iγ plasmids obtained fromEscherichia coliandSalmonella entericaisolates from animal and human reservoirs. For this, 251 IncI1-Iγ plasmids carrying various extended-spectrum β-lactamase (ESBL) or AmpC β-lactamase genes were compared using plasmid multilocus sequence typing (pMLST). Thirty-two of these plasmids belonging to different pMLST types were sequenced using Roche 454 and Illumina platforms. Epidemic IncI1-Iγ plasmids could be assigned to various dominant clades, whereas rarely detected plasmids clustered together as a distinct clade. Similar phylogenetic trees were obtained using only the plasmid backbone sequences, showing that the differences observed between the plasmids belonging to distinct clades resulted mainly from differences between their backbone sequences. Plasmids belonging to the various clades differed particularly in the presence/absence of genes encoding partitioning and addiction systems, which contribute to stable inheritance during cell division and plasmid maintenance. Despite this, plasmids belonging to the various phylogenetic clades also showed marked resistance gene associations, indicating the circulation of successful plasmid-gene combinations. The variation intraYandexcAgenes found in IncI1-Iγ plasmids is conserved within pMLST sequence types and plays a role in incompatibility, although functional study is needed to elucidate the role of these genes in plasmid epidemiology.

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Identification and Characterization of a Novel Genomic Island Integrated at selC in Locus of Enterocyte Effacement-Negative, Shiga Toxin-Producing Escherichia coli

Infection and Immunity ◽

10.1128/iai.69.11.6863-6873.2001 ◽

2001 ◽

Vol 69 (11) ◽

pp. 6863-6873 ◽

Cited By ~ 112

Author(s):

H. Schmidt ◽

W.-L. Zhang ◽

U. Hemmrich ◽

S. Jelacic ◽

W. Brunder ◽

...

Keyword(s):

Escherichia Coli ◽

Serine Protease ◽

Shiga Toxin ◽

Genomic Island ◽

Immunoblot Analysis ◽

Pcr Analysis ◽

Integrase Gene ◽

Human Apolipoprotein ◽

Genes Encoding ◽

Enterocyte Effacement

ABSTRACT The selC tRNA gene is a common site for the insertion of pathogenicity islands in a variety of bacterial enteric pathogens. We demonstrate here that Escherichia colithat produces Shiga toxin 2d and does not harbor the locus of enterocyte effacement (LEE) contains, instead, a novel genomic island. In one representative strain (E. coliO91:H− strain 4797/97), this island is 33,014 bp long and, like LEE in E. coli O157:H7, is integrated 15 bp downstream of selC. ThisE. coli O91:H− island contains genes encoding a novel serine protease, termed EspI; an adherence-associated locus, similar to iha ofE. coli O157:H7; an E.coli vitamin B12 receptor (BtuB); an AraC-type regulatory module; and four homologues of E.coli phosphotransferase proteins. The remaining sequence consists largely of complete and incomplete insertion sequences, prophage sequences, and an intact phage integrase gene that is located directly downstream of the chromosomal selC. Recombinant EspI demonstrates serine protease activity using pepsin A and human apolipoprotein A-I as substrates. We also detected Iha-reactive protein in outer membranes of a recombinant clone and 10 LEE-negative, Shiga toxin-producing E. coli (STEC) strains by immunoblot analysis. Using PCR analysis of various STEC, enteropathogenic E. coli, enterotoxigenicE. coli, enteroaggregativeE. coli, uropathogenic E.coli, and enteroinvasive E.coli strains, we detected the ihahomologue in 59 (62%) of 95 strains tested. In contrast,espI and btuB were present in only two (2%) and none of these strains, respectively. We conclude that the newly described island occurs exclusively in a subgroup of STEC strains that are eae negative and contain the variantstx 2d gene.

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Isolation and characterization of protease Do from Escherichia coli, a large serine protease containing multiple subunits

Archives of Biochemistry and Biophysics ◽

10.1016/0003-9861(83)90242-4 ◽

1983 ◽

Vol 224 (2) ◽

pp. 543-554 ◽

Cited By ~ 28

Author(s):

K.H.S. Swamy ◽

Chin Ha Chung ◽

Alfred L. Goldberg

Keyword(s):

Escherichia Coli ◽

Serine Protease ◽

Isolation And Characterization

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Purification and characterization of a Serratia marcescens nuclease produced by Escherichia coli

Carlsberg Research Communications ◽

10.1007/bf02910469 ◽

1989 ◽

Vol 54 (1) ◽

pp. 17-27 ◽

Cited By ~ 28

Author(s):

Kirsten Biedermann ◽

Pia Knak Jepsen ◽

Erik Riise ◽

Ib Svendsen

Keyword(s):

Escherichia Coli ◽

Serratia Marcescens ◽

Purification And Characterization

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Mechanism of interaction of an endofungal bacterium Serratia marcescens D1 with its host and non-host fungi

10.1101/796102 ◽

2019 ◽

Author(s):

Dibya Jyoti Hazarika ◽

Trishnamoni Gautom ◽

Assma Parveen ◽

Gunajit Goswami ◽

Madhumita Barooah ◽

...

Keyword(s):

Serratia Marcescens ◽

Type Vi Secretion System ◽

Major Area ◽

Fungal Cell ◽

Type Vi Secretion ◽

Mucor Irregularis ◽

Fungal Hyphae ◽

Genes Encoding ◽

Mechanism Of Interaction

AbstractAssociation of bacteria with fungi is a major area of research in infection biology, however, very few strains of bacteria have been reported that can invade and reside within fungal hyphae. Here, we report the characterization of an endofungal bacterium Serratia marcescens D1 from Mucor irregularis SS7 hyphae. Upon re-inoculation, colonization of the endobacterium S. marcescens D1 in the hyphae of Mucor irregularis SS7 was demonstrated using stereo microscopy. However, S. marcescens D1 failed to invade into the hyphae of the tested Ascomycetes (except Fusarium oxysporum) and Basidiomycetes. Remarkably, Serratia marcescens D1 could invade and spread over the culture of F. oxysporum that resulted in mycelial death. Prodigiosin, the red pigment produced by the Serratia marcescens D1, helps the bacterium to invade fungal hyphae as revealed by the increasing permeability in fungal cell membrane. On the other hand, genes encoding the type VI secretion system (T6SS) assembly protein TssJ and an outer membrane associated murein lipoprotein also showed significant up-regulation during the interaction process, suggesting the involvement of T6SS in the invasion process.

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Functional Differences between Heme Permeases: Serratia marcescens HemTUV Permease Exhibits a Narrower Substrate Specificity (Restricted to Heme) Than the Escherichia coli DppABCDF Peptide-Heme Permease

Journal of Bacteriology ◽

10.1128/jb.01636-07 ◽

2008 ◽

Vol 190 (6) ◽

pp. 1866-1870 ◽

Cited By ~ 12

Author(s):

Sylvie Létoffé ◽

Philippe Delepelaire ◽

Cécile Wandersman

Keyword(s):

Escherichia Coli ◽

Serratia Marcescens ◽

Outer Membrane Receptor ◽

Heme Uptake ◽

Periplasmic Binding Protein ◽

E Coli ◽

Iron Source ◽

Functional Differences ◽

Genes Encoding

ABSTRACT Serratia marcescens hemTUV genes encoding a potential heme permease were cloned in Escherichia coli recombinant mutant FB827 dppF::Km(pAM 238-hasR). This strain, which expresses HasR, a foreign heme outer membrane receptor, is potentially capable of using heme as an iron source. However, this process is invalidated due to a dppF::Km mutation which inactivates the Dpp heme/peptide permease responsible for heme, dipeptide, and δ-aminolevulinic (ALA) transport through the E. coli inner membrane. We show here that hemTUV genes complement the Dpp permease for heme utilization as an iron source and thus are functional in E. coli. However, hemTUV genes do not complement the Dpp permease for ALA uptake, indicating that the HemTUV permease does not transport ALA. Peptides do not inhibit heme uptake in vivo, indicating that, unlike Dpp permease, HemTUV permease does not transport peptides. HemT, the periplasmic binding protein, binds heme. Heme binding is saturable and not inhibited by peptides that inhibit heme uptake by the Dpp system. Thus, the S. marcescens HemTUV permease and, most likely, HemTUV orthologs present in many gram-negative pathogens form a class of heme-specific permeases different from the Dpp peptide/heme permease characterized in E. coli.

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Expression and Characterization of Streptococcal rgp Genes Required for Rhamnan Synthesis in Escherichia coli

Infection and Immunity ◽

10.1128/iai.70.6.2891-2898.2002 ◽

2002 ◽

Vol 70 (6) ◽

pp. 2891-2898 ◽

Cited By ~ 39

Author(s):

Yukie Shibata ◽

Yoshihisa Yamashita ◽

Kazuhisa Ozaki ◽

Yoshio Nakano ◽

Toshihiko Koga

Keyword(s):

Escherichia Coli ◽

Polyacrylamide Gel Electrophoresis ◽

Sodium Dodecyl ◽

Polymerization Process ◽

Streptococcus Sobrinus ◽

E Coli ◽

Genes Encoding ◽

Group A ◽

Specific Antigens

ABSTRACT Six genes (rgpA through rgpF) that were involved in assembling the rhamnose-glucose polysaccharide (RGP) in Streptococcus mutans were previously identified (Y. Yamashita, Y. Tsukioka, K. Tomihisa, Y. Nakano, and T. Koga, J. Bacteriol. 180:5803-5807, 1998). The group-specific antigens of Lancefield group A, C, and E streptococci and the polysaccharide antigen of Streptococcus sobrinus have the same rhamnan backbone as the RGP of S. mutans. Escherichia coli harboring plasmid pRGP1 containing all six rgp genes did not synthesize complete RGP. However, E. coli carrying a plasmid with all of the rgp genes except for rgpE synthesized the rhamnan backbone of RGP without glucose side chains, suggesting that in addition to rgpE, another gene is required for glucose side-chain formation. Synthesis of the rhamnan backbone in E. coli required the initiation of transfer of N-acetylglucosamine to a lipid carrier and the expression of the rgpC and rgpD genes encoding the putative ABC transporter specific for RGP. The similarities in RGP synthesis between E. coli and S. mutans suggest common pathways for rhamnan synthesis. Therefore, we evaluated the rhamnosyl polymerization process in E. coli by high-resolution sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the lipooligosaccharide (LOS). An E. coli transformant harboring rgpA produced the LOS modified by the addition of a single rhamnose residue. Furthermore, the rgpA, rgpB, and rgpF genes of pRGP1 were independently mutated by an internal deletion, and the LOS chemotypes of their transformants were examined. The transformant with an rgpA deletion showed the same LOS profile as E. coli without a plasmid. The transformant with an rgpB deletion showed the same LOS profile as E. coli harboring rgpA alone. The transformant with an rgpF deletion showed the LOS band with the most retarded migration. On the basis of these results, we speculated that RgpA, RgpB, and RgpF, in that order, function in rhamnan polymerization.

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