CHANGES IN WALL TEICHOIC-ACID DURING THE ROD-SPHERE TRANSITION OF BACILLUS-SUBTILIS-168

Wall teichoic acid (WTA) is essential for the growth of Bacillus subti lis 168. To clarify the function of this polymer, the WTAs of strains 168, 104 rodB1, and 113 tagF1(rodC1) grown at 32 and 42 degrees C were characterized. At the restrictive temperature, the rodB1I and tagF1(r odC1) mutants undergo a rod-to-sphere transition that is correlated wi th changes in the WTA content of the cell wall. The amount of WTA decr eased 33% in strain 104 rodB1 and 84% in strain 113 tagF1(rodC1) when they were grown at the restrictive temperature. The extent of alpha-D- glucosylation (0.84) was not affected by growth at the higher temperat ure in these strains. The degree of D-alanylation decreased from 0.22 to 0.10 in the rodB1 mutant but remained constant (0.12) in the tagF1 (rodC1) mutant at both temperatures. Under these conditions, the degre e of D-alanylation in the parent strain decreased from 0.27 to 0.21. T he chain lengths of WTA in strains 168 and 104 rodB1 grown at both tem peratures were approximately 53 residues, with a range of 45 to 60. In contrast, although the chain length of RTA from the tagF1(rodC1) muta nt at 32 degrees C was similar to that of strains 168 and 104 rodB1, i t was approximately eight residues at the restrictive temperature. The results suggested that the rodB1 mutant is partially deficient in com pleted poly(glycerophosphate) chains. The precise biochemical defect i n this mutant remains to be determined. The results for strain 113 tag F1(rodC1) are consistent with the temperature-sensitive defect in the CDP-glycerol:poly(glycerophosphate) glycerophosphotransferase (H. M. P ooley, F.-X. Abellan, and D. Karamata, J. Bacteriol. 174:646-649, 1992 ).