390
E. A. FREUNDT EI‘ AL.
the interpretation of results obtained in serodiagnostic or sero-epidemiological surveys by other methods such as CF and IHA tests. For example,
the fact that the CF test has proved specific for diagnosing M. pneumoniue
pneumonia correlates with its uniqueness as shown by inimunodiffusion
tests ; this species apparently shares no common antigens with other
mycoplasmas from man.
Double immunodiffusion tests as usually carried out are less speciesspecific than GI, MI or immunofluorescence, and this is probably because
cytoplasmic antigens are involved. I n tests employing ultrasonically treated
or frozen-thawed suspensions and adjuvant-produced sera, reactions seem
to be due mainly to cytoplasmic antigens, although surface coniponents
which are easily released from the membrane may be involved. When
suspensions are treated with detergents, at least two additional precipitin
bands released by lysis of the membrane are observed. It appears that
cytoplasmic antigens are less species-specific than membrane antigens.
Within a single species, it is antigens in the membrane rather than the
cytoplasmic fraction that, in immunodiffusion tests, reveal differences
between strains (Hollingdale and Lemcke, 1970).
D. Subspecies
At present only one species is subdivided into the lower category of subspecies, viz. M . mycoides. It has been a matter of discussion, however, for a
long time whether the subspecies concerned might not rather deserve the
rank of species. Whatever the final decision may be in this case, a subdivision of some other species may well be necessary in the future since an
increasing number of isolates are being analysed and biochemical methods
are being refined and standardised. A further subdivision based on the
infrasubspecific terms serotype, chemotype and biotype (equivalent to the
recently proposed terms “serovar”, “chemovar” and “biovar” (Lepage
et ul., 1973, Appendix 10)) might then be taken into consideration.
E. Present status of classification into species and subspecies
I n Table I1 are listed the species and subspecies of the genus Mycoplamnu
recognised at present, together with their type strains, a medium found
suitable for the growth of each species, and some biochemical characteristics.
The number of strains examined for each species or subspecies is in some
cases so small that future investigations may well reveal biochemical
variants. Taxonomic references are given for those species which are not
included in the 8th edition of “Bergey’s Manual of Determinative Bacteriology” (Freundt, 1974~).
E. A. FREUNDT EI‘ AL.
the interpretation of results obtained in serodiagnostic or sero-epidemiological surveys by other methods such as CF and IHA tests. For example,
the fact that the CF test has proved specific for diagnosing M. pneumoniue
pneumonia correlates with its uniqueness as shown by inimunodiffusion
tests ; this species apparently shares no common antigens with other
mycoplasmas from man.
Double immunodiffusion tests as usually carried out are less speciesspecific than GI, MI or immunofluorescence, and this is probably because
cytoplasmic antigens are involved. I n tests employing ultrasonically treated
or frozen-thawed suspensions and adjuvant-produced sera, reactions seem
to be due mainly to cytoplasmic antigens, although surface coniponents
which are easily released from the membrane may be involved. When
suspensions are treated with detergents, at least two additional precipitin
bands released by lysis of the membrane are observed. It appears that
cytoplasmic antigens are less species-specific than membrane antigens.
Within a single species, it is antigens in the membrane rather than the
cytoplasmic fraction that, in immunodiffusion tests, reveal differences
between strains (Hollingdale and Lemcke, 1970).
D. Subspecies
At present only one species is subdivided into the lower category of subspecies, viz. M . mycoides. It has been a matter of discussion, however, for a
long time whether the subspecies concerned might not rather deserve the
rank of species. Whatever the final decision may be in this case, a subdivision of some other species may well be necessary in the future since an
increasing number of isolates are being analysed and biochemical methods
are being refined and standardised. A further subdivision based on the
infrasubspecific terms serotype, chemotype and biotype (equivalent to the
recently proposed terms “serovar”, “chemovar” and “biovar” (Lepage
et ul., 1973, Appendix 10)) might then be taken into consideration.
E. Present status of classification into species and subspecies
I n Table I1 are listed the species and subspecies of the genus Mycoplamnu
recognised at present, together with their type strains, a medium found
suitable for the growth of each species, and some biochemical characteristics.
The number of strains examined for each species or subspecies is in some
cases so small that future investigations may well reveal biochemical
variants. Taxonomic references are given for those species which are not
included in the 8th edition of “Bergey’s Manual of Determinative Bacteriology” (Freundt, 1974~).