The priB gene of Klebsiella pneumoniae encodes a 104-amino acid protein that is similar in structure and function to Escherichia coli PriB

• Published in: PloS one Vol. 6; no. 9; p. e24494
• Main Authors: Berg, Linda, Lopper, Matthew E
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 08.09.2011; Public Library of Science (PLoS)
• Subjects: Acids; Amino Acid Sequence; Amino acids; Analysis; Bacteria; Bacterial Proteins - chemistry; Biology; Chromatography, Gel; Deoxyribonucleic acid; DNA; DNA binding; DNA biosynthesis; DNA damage; DNA helicase; DNA replication; DNA-binding protein; DNA-Binding Proteins - chemistry; DNA-Binding Proteins - metabolism; E coli; Escherichia coli; Escherichia coli - metabolism; Escherichia coli Proteins - chemistry; Gel filtration; Genes; Genetic engineering; Genomes; Homology; Identification; Klebsiella; Klebsiella pneumoniae; Klebsiella pneumoniae - metabolism; Molecular Sequence Data; Pectobacterium carotovorum; Pneumonia; PriA protein; PriB gene; Protein Binding; Protein Structure, Quaternary; Protein Structure, Tertiary; Proteins; Residues; Salmonella; Salmonella Typhimurium; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Single-stranded DNA; Single-stranded DNA-binding protein; Species Specificity; Structure-function relationships; Temperature; Yersinia; Ohio
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0024494

Primosome protein PriB is a single-stranded DNA-binding protein that serves as an accessory factor for PriA helicase-catalyzed origin-independent reinitiation of DNA replication in bacteria. A recent report describes the identification of a novel PriB protein in Klebsiella pneumoniae that is significantly shorter than most sequenced PriB homologs. The K. pneumoniae PriB protein is proposed to comprise 55 amino acid residues, in contrast to E. coli PriB which comprises 104 amino acid residues and has a length that is typical of most sequenced PriB homologs. Here, we report results of a sequence analysis that suggests that the priB gene of K. pneumoniae encodes a 104-amino acid PriB protein, akin to its E. coli counterpart. Furthermore, we have cloned the K. pneumoniae priB gene and purified the 104-amino acid K. pneumoniae PriB protein. Gel filtration experiments reveal that the K. pneumoniae PriB protein is a dimer, and equilibrium DNA binding experiments demonstrate that K. pneumoniae PriB's single-stranded DNA-binding activity is similar to that of E. coli PriB. These results indicate that the PriB homolog of K. pneumoniae is similar in structure and in function to that of E. coli.