Functional characterization of TcaA: minimal requirement for teicoplanin susceptibility and role in Caenorhabditis elegans virulence.
The inactivation of TcaA contributes to intrinsic teicoplanin resistance in experimental and clinical isolates of glycopeptide-intermediate resistant Staphylococcus aureus. PhoA fusions confirmed that TcaA is a transmembrane protein with a short intracellular N-terminal domain containing a C-4 zinc finger binding motif, a single membrane-spanning domain, and a large extracellular C-terminal domain. The region conferring teicoplanin susceptibility was narrowed down to the transmembrane part and the first third of the extracellular domain of TcaA, suggesting that neither the C-4 zinc finger binding motif nor the C terminus contributed to teicoplanin susceptibility. TcaA belongs to the cell wall stress stimulon, which comprises a set of genes universally upregulated by cell wall damage. Induction of tcaA was shown to be fully dependent on the two-component regulatory system VraSR. A 66-bp region upstream of the transcriptional start site, which contained an inverted repeat partially covering the promoter box, was shown to be essential for VraSR-mediated induction by cell wall stress. Interestingly, the induction or overexpression of tcaA did not contribute further to teicoplanin susceptibility, suggesting that small amounts of TcaA, such as those present under normal uninduced conditions, were sufficient for TcaA-mediated teicoplanin susceptibility. The strong attenuation of tcaA deletion mutants in a Caenorhabditis elegans survival assay suggested that TcaA may, in addition to affecting glycopeptide susceptibility, also play a role in virulence.
McCallum
Nadine
N
Institute of Medical Microbiology, University of Zurich, Gloriastr. 32, 8006 Zurich, Switzerland. mccallum@immv.uzh.ch
Brassinga
Ann Karen C
AK
Sifri
Costi D
CD
Berger-Bächi
Brigitte
B
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D017173:Caenorhabditis elegans / Q000382:microbiology*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005816:Genetic Complementation Test; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D009154:Mutation; D011401:Promoter Regions, Genetic / Q000235:genetics; D013211:Staphylococcus aureus / Q000235:genetics* / Q000472:pathogenicity; D016019:Survival Analysis; D017334:Teicoplanin / Q000494:pharmacology*; D014774:Virulence / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D008565:Membrane Proteins; D017334:Teicoplanin
Proc Natl Acad Sci U S A. 2002 Mar 5;99(5):2690-5
11867724
Bioinformatics. 2001 Sep;17(9):849-50
11590105
Infect Immun. 2003 Apr;71(4):2208-17
12654843
Biochim Biophys Acta. 2003 May 2;1621(2):117-21
12726988
Mol Microbiol. 2003 Aug;49(3):807-21
12864861
J Bacteriol. 2003 Aug;185(15):4638-43
12867477
Antimicrob Agents Chemother. 2003 Aug;47(8):2558-64
12878519
Microbiology. 2003 Oct;149(Pt 10):2719-32
14523105
J Mol Biol. 2004 May 14;338(5):1027-36
15111065
J Bacteriol. 2004 May;186(10):2966-72
15126456
Antimicrob Agents Chemother. 2004 Jun;48(6):1953-9
15155184
Mol Microbiol. 2004 Aug;53(4):1221-31
15306023
Proc Natl Acad Sci U S A. 2004 Aug 17;101(33):12312-7
15304642
Genetics. 1974 May;77(1):71-94
4366476
J Bacteriol. 1983 Apr;154(1):366-74
6339478
Nature. 1983 Oct 20-26;305(5936):709-12
6226876
J Biol Chem. 1994 Nov 18;269(46):28822-8
7961839
Nucleic Acids Res. 1995 Aug 25;23(16):3357-8
7545288
Protein Eng. 1997 Jun;10(6):673-6
9278280
Microb Drug Resist. 1998 Fall;4(3):159-68
9818967
Antimicrob Agents Chemother. 1999 Feb;43(2):240-5
9925512
J Biol Chem. 1999 Jul 2;274(27):18942-6
10383392
Antimicrob Agents Chemother. 2004 Dec;48(12):4800-7
15561859
Infect Immun. 2005 Feb;73(2):872-7
15664928
J Bacteriol. 2005 Apr;187(7):2426-38
15774886
Antimicrob Agents Chemother. 2005 Aug;49(8):3404-13
16048954
Intern Med J. 2005 Dec;35 Suppl 2:S136-40
16271057
Clin Infect Dis. 2006 Jan 1;42 Suppl 1:S25-34
16323116
Clin Infect Dis. 2006 Jan 1;42 Suppl 1:S40-50
16323119
Plasmid. 2006 Jan;55(1):58-63
16051359
Infect Immun. 2006 Feb;74(2):1091-6
16428756
J Bacteriol. 2006 Feb;188(3):1120-33
16428416
Clin Microbiol Infect. 2006 Mar;12 Suppl 1:16-23
16445720
Antimicrob Agents Chemother. 2006 Jul;50(7):2352-60
16801412
Biochim Biophys Acta. 2006 Oct;1760(10):1475-81
16891058
PLoS Pathog. 2007 Apr;3(4):e57
17447841
Biochem Biophys Res Commun. 2000 Mar 16;269(2):485-90
10708580
Biochim Biophys Acta. 2000 Oct 18;1523(2-3):135-9
11042376
FEMS Microbiol Lett. 2001 Jan 1;194(1):77-82
11150669
Lancet. 2001 Apr 21;357(9264):1225-40
11418146
J Clin Microbiol. 2001 Jul;39(7):2439-44
11427551
J Chem Inf Comput Sci. 2002 May-Jun;42(3):620-32
12086524