Genetic and antigenic distinction of Mycoplasma pirum from other mycoplasmas with specialized tip structures

The recently established species Mycoplasma pirum was examined for possible genetic and antigenic relatedness to the morphologically similar species Mycoplasma genitalium and Mycoplasma pneumoniae. The results of electrophoretic analysis of cell proteins, deoxyribonucleic acid (DNA) cleavage by restriction endonucleases, Southern blot analysis of digested mycoplasmal DNA with ribosomal ribonucleic acid genes and with total genomic DNA as probes, and Western immunoblot analysis rule out any significant degree of genetic relatedness between M. pirum and the other two mycoplasmas, in contrast to the marked antigenic relatedness of M. genitalium to M. pneumoniae. The value of the above molecular tools in resolving taxonomic problems at the species level is demonstrated.