Occurrence and regulation of the ferric citrate transport system in Escherichia coli B, Klebsiella pneumoniae, Enterobacter aerogenes, and Photorhabdus luminescens

被引:28
作者
Mahren, S [1 ]
Schnell, H [1 ]
Braun, V [1 ]
机构
[1] Univ Tubingen, D-72076 Tubingen, Germany
关键词
FecIRA; transmembrane transcription control; surface signaling; Escherichia coli B; Klebsiella pneumoniae; Enterobacter aerogenes; Photorhabdus luminescens; virulence plasmid;
D O I
10.1007/s00203-005-0035-y
中图分类号
Q93 [微生物学];
学科分类号
071005 ; 100705 ;
摘要
In Escherichia coli K-12, transcription of the ferric citrate transport genes fecABCDE is initiated by binding of diferric dicitrate to the outer membrane protein FecA which elicits a signaling cascade from the cell surface to the cytoplasm. The FecI sigma factor is only active in the presence of FecR, which transfers the signal across the cytoplasmic membrane. In other bacteria, fecIRA homologues control iron transport gene transcription by siderophores other than citrate. However, in most cases, the FecI homologues are active in the absence of the FecR homologues, which might function as anti-sigma factors. Since not all E. coli strains contain a fec system, we determined the occurrence of fec genes in selected Enterobacteriaceae and the dependence of FecI activity on FecR. Incomplete FecIRA systems were chromosomally encoded in Enterobacter aerogenes strains and plasmid-encoded in K. pneumoniae. E. coli B, Photorhabdus luminescens and one of three Klebsiella pneumoniae strains had a functional FecIRA regulatory system as in E. coli K-12. The cytoplasmic N-terminal FecR fragments caused constitutive FecI activity in the absence of ferric citrate. The PCR-generated mutant FecI(D40G) was inactive and FecI(S15P) was partially active. FecR of E. coli K-12 activated FecI of all tested strains except FecI encoded on the virulence plasmid pLVPK of K. pneumoniae, which differed from E. coli K-12 FecI by having mutations in region 4, which is important for interaction with FecR. The C-terminally truncated FecR homologue of pLVPK was inactive. pLVPK-encoded FecA contains a 38-residue sequence in front of the signal sequence that did not prevent processing and proper integration of FecA into the outer membrane of E. coli and lacks the signaling sequence required for transcription initiation of the fec transport genes, making it induction-incompetent but transport-competent. The evidence indicates that fecIRABCDE genes are acquired by horizontal DNA transfer and can undergo debilitating mutations.
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页码:175 / 186
页数:12
相关论文
共 44 条
[1]   TRANSCRIPTIONAL REGULATION OF FERRIC CITRATE TRANSPORT IN ESCHERICHIA-COLI K-12 - FECL BELONGS TO A NEW SUBFAMILY OF SIGMA(70)-TYPE FACTORS THAT RESPOND TO EXTRACYTOPLASMIC STIMULI [J].
ANGERER, A ;
ENZ, S ;
OCHS, M ;
BRAUN, V .
MOLECULAR MICROBIOLOGY, 1995, 18 (01) :163-174
[2]   Iron regulates transcription of the Escherichia coli ferric citrate transport genes directly and through the transcription initiation proteins [J].
Angerer, A ;
Braun, V .
ARCHIVES OF MICROBIOLOGY, 1998, 169 (06) :483-490
[3]   The complete genome sequence of Escherichia coli K-12 [J].
Blattner, FR ;
Plunkett, G ;
Bloch, CA ;
Perna, NT ;
Burland, V ;
Riley, M ;
ColladoVides, J ;
Glasner, JD ;
Rode, CK ;
Mayhew, GF ;
Gregor, J ;
Davis, NW ;
Kirkpatrick, HA ;
Goeden, MA ;
Rose, DJ ;
Mau, B ;
Shao, Y .
SCIENCE, 1997, 277 (5331) :1453-+
[4]   Regulation of the Fecl-type ECF sigma factor by transmembrane signalling [J].
Braun, V ;
Mahren, S ;
Ogierman, M .
CURRENT OPINION IN MICROBIOLOGY, 2003, 6 (02) :173-180
[5]  
BRAUN V, 1995, FEMS MICROBIOL REV, V16, P295, DOI 10.1016/0168-6445(95)00003-U
[6]   A signal transfer system through three compartments transduces the plant cell contact-dependent signal controlling Ralstonia solanacearum hrp genes [J].
Brito, B ;
Aldon, D ;
Barberis, P ;
Boucher, C ;
Genin, S .
MOLECULAR PLANT-MICROBE INTERACTIONS, 2002, 15 (02) :109-119
[7]   Sequencing and analysis of the large virulence plasmid pLVPK of Klebsiella pneumoniae CG43 [J].
Chen, YT ;
Chang, HY ;
Lai, YC ;
Pan, CC ;
Tsai, SF ;
Peng, HL .
GENE, 2004, 337 :189-198
[8]   Photobactin:: a catechol siderophore produced by Photorhabdus luminescens, an entomopathogen mutually associated with Heterorhabditis bacteriophora NC1 nematodes [J].
Ciche, TA ;
Blackburn, M ;
Carney, JR ;
Ensign, JC .
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, 2003, 69 (08) :4706-4713
[9]   The genome sequence of the entomopathogenic bacterium Photorhabdus luminescens [J].
Duchaud, E ;
Rusniok, C ;
Frangeul, L ;
Buchrieser, C ;
Givaudan, A ;
Taourit, S ;
Bocs, S ;
Boursaux-Eude, C ;
Chandler, M ;
Charles, JF ;
Dassa, E ;
Derose, R ;
Derzelle, S ;
Freyssinet, G ;
Gaudriault, S ;
Médigue, C ;
Lanois, A ;
Powell, K ;
Siguier, P ;
Vincent, R ;
Wingate, V ;
Zouine, M ;
Glaser, P ;
Boemare, N ;
Danchin, A ;
Kunst, F .
NATURE BIOTECHNOLOGY, 2003, 21 (11) :1307-1313
[10]   Sites of interaction between the FecA and FecR signal transduction proteins of ferric citrate transport in Escherichia coli K-12 [J].
Enz, S ;
Brand, H ;
Orellana, C ;
Mahren, S ;
Braun, V .
JOURNAL OF BACTERIOLOGY, 2003, 185 (13) :3745-3752