Triton X-114 phase partitioning of M. agalactiae type strain PG2. (A) Mycoplasmas at the end of exponential growth were subjected to Triton X-114 partitioning; 15 μl of fractions and total antigen were separated on SDS-12% acrylamide gels, transferred to a nitrocellulose filter, and probed with monospecific P40 antiserum. Lane 1, total antigen; lane 2, detergent phase; lane 3, aqueous phase. (B) Western blot analysis of Triton X-114 extract from PG2 with serum PAL 97 (lane 1) and serum anti-P40 (lane 2).