Functional diversity of three different DsbA proteins from Neisseria meningitidis.
The genome of Neisseria meningitidis serogroup B strain MC58 contains three genes - nmb0278, nmb0294 and nmb0407 - encoding putative homologues of DsbA, a periplasmic thiol disulphide oxidoreductase protein-folding catalyst of the Dsb protein family. DsbA assists the folding of periplasmic and membrane proteins in diverse organisms. While all three cloned genes complemented the DTT sensitivity of dsbA-null Escherichia coli, they showed different activities in folding specific target proteins in this background. NMB0278 protein was the most active in complementing defects in motility and alkaline phosphatase activity, while NMB0294 was the most active in folding periplasmic MalF. NMB0407 showed the weakest activity in all assays. It is extremely unusual for organisms to contain more than one chromosomal dsbA. Among the members of the genus Neisseria, only the meningococcus carries all three of these genes. Strains of Neisseria gonorrhoeae, Neisseria lactamica, Neisseria cinerea and Neisseria polysaccharea contained only homologues of nmb0278 and nmb0407, while Neisseria flava, Neisseria subflava and Neisseria flavescens carried only nmb0294. It is speculated that the versatility of the meningococcus in surviving in different colonizing and invasive disease settings may be derived in part from an enhanced potential to deploy outer-membrane proteins, a consequence of carrying an extended repertoire of protein-folding catalysts.
Sinha
Sunita
S
Molecular Infectious Diseases Group, Department of Paediatrics, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
Langford
Paul R
PR
Molecular Infectious Diseases Group, Department of Paediatrics, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
Kroll
J Simon
JS
Molecular Infectious Diseases Group, Department of Paediatrics, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
D018528:ATP-Binding Cassette Transporters / Q000378:metabolism; D000469:Alkaline Phosphatase / Q000378:metabolism; D000595:Amino Acid Sequence; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D004226:Dithioerythritol / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000502:physiology; D029968:Escherichia coli Proteins / Q000378:metabolism; D017353:Gene Deletion; D005816:Genetic Complementation Test; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins / Q000378:metabolism; D009068:Movement; D009343:Neisseria / Q000235:genetics; D042804:Neisseria cinerea / Q000235:genetics; D009344:Neisseria gonorrhoeae / Q000235:genetics; D042806:Neisseria lactamica / Q000235:genetics; D009345:Neisseria meningitidis / Q000201:enzymology* / Q000235:genetics*; D019704:Protein Disulfide-Isomerases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D017510:Protein Folding; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D017385:Sequence Homology
D018528:ATP-Binding Cassette Transporters; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D007527:Isoenzymes; C461639:MalF protein, E coli; D009004:Monosaccharide Transport Proteins; D011993:Recombinant Fusion Proteins; D004226:Dithioerythritol; D000469:Alkaline Phosphatase; D019704:Protein Disulfide-Isomerases