Genetic and biochemical characterization of Bacillus subtilis 168 mutants specifically blocked in the synthesis of the teichoic acid poly(3-O-beta-D-glucopyranosyl-N-acetylgalactosamine 1-phosphate): gneA, a new locus, is associated with UDP-N-acetylglucosamine 4-epimerase activity.
The resistance spectrum to bacteriophage phi 3T of different Bacillus subtilis 168/W23 strains hybrid for wall teichoic acids suggested that poly(3-O-beta-D-glucopyranosyl-N-acetylgalactosamine 1-phosphate), a so-called minor teichoic acid of strain 168, forms part of the receptor for this phage, and a serologically related group of phages. A representative sample of 25 mutants specifically resistant to phi 3T, obtained from a mutagenized culture by direct selection, were all found to have a greatly reduced galactosamine content. Relevant mutations in these strains were shown by PBS1 transduction and transformation to belong to two linkage groups; a minority, associated with an atypical colony morphology, were localized between sacA and purA, whereas the majority mapped between gtaB and tagB1 (formerly tag-1), a region containing all known genes involved in the synthesis of the major wall teichoic acid, poly(glycerol phosphate). The former mutations mapped in a new locus, gneA, characterized by a deficiency in UDP-N-acetylglucosamine 4-epimerase, while the latter ones, as well as the previously identified pha-3 (Estrela et al., 1986, Journal of General Microbiology 132, 411-415), map is a locus named gga. They are likely to affect membrane-bound enzymes involved in the synthesis of the galactosamine-containing teichoic acid. A possible biological role of this polymer is discussed.
Estrela
A I
AI
Institut de Génétique et de Biologie Microbiennes, Lausanne, Switzerland.
Pooley
H M
HM
de Lencastre
H
H
Karamata
D
D
D000327:Adsorption; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D001435:Bacteriophages / Q000502:physiology; D002238:Carbohydrate Epimerases / Q000235:genetics* / Q000378:metabolism; D002240:Carbohydrate Sequence; D002874:Chromosome Mapping; D005798:Genes, Bacterial; D008040:Genetic Linkage; D008969:Molecular Sequence Data; D016296:Mutagenesis; D009154:Mutation; D013682:Teichoic Acids / Q000235:genetics* / Q000378:metabolism; D014161:Transduction, Genetic
D013682:Teichoic Acids; C070078:poly(3-O-beta-glucopyranosyl-N-acetylgalactosamine 1-phosphate); D002238:Carbohydrate Epimerases; C023223:UDP-N-acetylglucosamine 4-epimerase