title: Evidence for the bacterial origin of Acholeplasma laidlawii A.
abstract: L-forms from a Corynebacterium were induced in hyperosmolar media and gradually adapted to normal osmolarity over a period of two years. During this adaptation several morphologic L-form variants derived from the L-form cultures and were serologically identified as Acholeplasma laidlawii A. The possibility that the bacterial and L-form cultures were contaminated with acholeplasmas was carefully investigated; this was determined not to be the case. Membrane protein gel electrophoresis patterns of these L-form variants were identical to the ATCC A. laidlawii strain PG-8. Acholeplasma phage MVL-1 displayed no affinity for these L-form variants. Phage MVL-2 showed low affinity, but after virus enhancement in the specific host, high plaquing efficiency ensued. DNA hybridization experiments showed a high level of nucleotide sequence homology (greater than 90%) between the L-form-derived variants and PG-8. The homology between the diphtheroid L-forms and the PG-8 strain was 16.4% with te50 values of 86%; this indicates strong base pairing homology. These findings suggest that the L-form variants are acholeplasmas and that they are biologically and genetically related to the Corynebacterium L-forms.
mesh_terms: D000128:Acholeplasma laidlawii / Q000145:classification / Q000166:cytology / Q000235:genetics / Q000502:physiology*; D001426:Bacterial Proteins / Q000032:analysis; D001435:Bacteriophages; D001482:Base Composition; D001483:Base Sequence; D003352:Corynebacterium / Q000166:cytology* / Q000254:growth & development; D004269:DNA, Bacterial / Q000032:analysis; D006801:Humans; D007740:L Forms / Q000145:classification / Q000235:genetics / Q000502:physiology*; D008565:Membrane Proteins / Q000032:analysis; D009693:Nucleic Acid Hybridization; D009994:Osmolar Concentration; D012698:Serologic Tests; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008565:Membrane Proteins; D012965:Sodium Chloride