title: Overexpresssion of a Legionella pneumophila homologue of the E. coli regulator csrA affects cell size, flagellation, and pigmentation.
abstract: Legionella pneumophila is an inhabitant of the aquatic environment and the causative agent of a bacterial pneumonia. We identified the presence of an L. pneumophila homologue of csrA of E. coli and rsmA of Erwinia carotovora, genes which regulate gene expression by destabilising mRNA and which have been shown to relate to environmental fitness and pathogenicity. The Legionella csrA was able to complement a csrA-negative mutant of E. coli. Overproduction of csrA in L. pneumophila lead to a reduction of flagellation and pigmentation and an increase in bacterial cell size. csrA overproduction was associated with a reduction of fliA and flaA transcripts. This suggests that similar to E. coli and Erwinia, L. pneumophila csrA is a regulator of gene expression and may contribute to the capability of the pathogen to rapidly adapt to changing environments.
authors.affiliation: Department of Medical Microbiology and Hygiene, University of Ulm, Germany.
authors.forename: P S
authors.initials: PS
authors.lastname: Fettes
authors.forename: V
authors.initials: V
authors.lastname: Forsbach-Birk
authors.forename: D
authors.initials: D
authors.lastname: Lynch
authors.forename: R
authors.initials: R
authors.lastname: Marre
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000502:physiology; D001483:Base Sequence; D015152:Blotting, Northern; D015153:Blotting, Western; D048429:Cell Size / Q000235:genetics; D003470:Culture Media; D004926:Escherichia coli / Q000235:genetics; D029968:Escherichia coli Proteins; D005407:Flagella / Q000235:genetics; D005408:Flagellin / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial; D005816:Genetic Complementation Test; D006003:Glycogen / Q000096:biosynthesis; D016952:Legionella pneumophila / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D016973:Pectobacterium carotovorum / Q000235:genetics; D010641:Phenotype; D010860:Pigments, Biological / Q000378:metabolism; D010957:Plasmids / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000502:physiology; D012097:Repressor Proteins / Q000235:genetics / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D012808:Sigma Factor / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; C093587:CsrA protein, E coli; D003470:Culture Media; D029968:Escherichia coli Proteins; C064971:FliA protein, Bacteria; D010860:Pigments, Biological; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D012097:Repressor Proteins; C095468:RsmA protein, Erwinia carotovora; D012808:Sigma Factor; D005408:Flagellin; C067138:flaA protein, bacteria; D006003:Glycogen