Two-dimensional gel electrophoresis of ribosomal proteins from Propionibacterium acnes and granulosum.

Ribosomal proteins (r-proteins) from a type I strain (ATCC 11827) and a type II strain (ATCC 11828) of Propionibacterium acnes (P. acnes) and from a Propionibacterium granulosum (P. granulosum) strain (ATCC 11829-2) were analyzed using two-dimensional polyacrylamide gel electrophoresis (two-dimensional PAGE), for the purpose of genetical analysis of the P. acnes type I and type II strains and the P. granulosum strain. Among the fifty r-proteins in all, almost all of the proteins were electrophoretically different between both of the two types of P. acnes strains and the P. granulosum strain, whereas only five proteins were different between the type I and type II strains of P. acnes. Such differences of r-protein composition between the type I and type II strains of P. acnes indicate that the type I strain is genetically different from, but very closely related to, the type II strain. However, the P. granulosum strain is not so closely related to both the two types of P. acnes strains. This study thus suggests that the two-dimensional PAGE of r-proteins is an excellent tool for the taxonomy of P. acnes and the related bacteria.