>Is Mycobacterium considered an actinomycete?
This may not be the latest opinion but, the last time I looked at Bergey,
the family Mycobacteriaceae, which contains the genus Mycobacterium was one
of the ten families comprising the actinomycetes. Seven of these families
are classed as true actinomycetes (permanent mycelium, spores and
sporangia). The other three families are "proactinomycetes" (families
Mycobacteriaceae, Actinomycetaceaea and Nocardiaceae) which to put it
crudely "have a go" at producing the structural complexity of the true
actinomycetes but dont really make it ! Mycobacterium is particularly
poor in this respect. The position of the proactinomycetes seems justified
by several characteristics that they share with the true actinomycetes (DNA
base composition, diaminopimelic acid in the cell wall), but (as is not
unusual when dealing with microbial taxonomy) things are slightly more
complex than they may at first appear. One of the proactinomycetes
(Actinomyces) has lysine insted of DAP in its cell wall, and the
proactinomycetes have characteristics in common with members of the
coryneform group.
John W. Patching
The Martin Ryan Marine Science Institute
University College Galway, Ireland
Email: John.Patching at UCG.IE
Phone: +353-91-24411 Ext 2398
Fax: +353-91-750456 or +353-91-525005
