Functional and genetic characterization of mcpC, which encodes a third methyl-accepting chemotaxis protein in Bacillus subtilis.
A 3135 bp DNA segment downstream of the spl gene on the Bacillus subtilis chromosome was cloned and its nucleotide sequence determined. An open reading frame capable of encoding a putative protein of 654 amino acids with a calculated molecular mass of 72.1 kDa was identified. The deduced amino acid sequence was similar to the McpA and McpB proteins of B. subtilis. McpA and McpB encode different methyl-accepting chemotaxis proteins (MCPs). A mutant strain containing an antibiotic resistance DNA cassette inserted into the region containing the MCP-like reading frame suffered a complete loss of taxis to the amino acids cysteine, proline, threonine, glycine, serine, lysine, valine and arginine. The open reading frame was designated mcpC. The wild-type and an mcpC mutant strain were analysed for their content of methylated proteins and it was found that mcpC encodes a methylated membrane protein that has previously been designated H3. These results show that mcpC encodes a third MCP in B. subtilis. The transcription start site upstream of the mcpC gene was determined by primer extension analysis and it was found to be preceded by a potential promoter sequence that is recognized by the sigma D form of RNA polymerase. The level of beta-galactosidase expressed from a transcriptional mcpC-lacZ fusion was increased threefold when cells entered the stationary phase. No beta-galactosidase could be detected in a sigD genetic background.
Müller
Jakob
J
Department of Microbiology, Technical University of Denmark, Bldg 301, DK-2800 Lyngby, Denmark.
Schiel
Stacey
S
Department of Biochemistry, University of Illinois, 190 Medical Sciences Bldg, 506 S. Mathews Ave, Urbana, IL 61801-3618, USA.
Ordal
George W
GW
Department of Biochemistry, University of Illinois, 190 Medical Sciences Bldg, 506 S. Mathews Ave, Urbana, IL 61801-3618, USA.
Saxild
Hans H
HH
Department of Microbiology, Technical University of Denmark, Bldg 301, DK-2800 Lyngby, Denmark.
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics* / Q000502:physiology; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002633:Chemotaxis / Q000235:genetics*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D015870:Gene Expression; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics*; D000072236:Methyl-Accepting Chemotaxis Proteins; D008969:Molecular Sequence Data; D009154:Mutation; D016366:Open Reading Frames
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008565:Membrane Proteins; D000072236:Methyl-Accepting Chemotaxis Proteins