316
M. A. GERENCSER
at pH 8.6. They can be detected in acid and autoclave extracts of whole
cells as well as in purified wall preparations.
The charged antigens (group 2) are more complex than the group 1
antigens. The charged antigens were trypsin resistant, pronase sensitive,
and acid and heat stable. Trypsin-treated cell walls seemed to contain both
groups of antigens, but pronase-treated walls contained only the group 1
antigens. Charged antigens from acid extracts were very similar to culture
medium supernate antigens and showed a more complex pattern in
precipitin tests than autoclave extracts.
Fractionation of the wall carbohydrate antigens of A. israelii yielded
two components, one which was serotype 2 specific and one which crossreacted with serotype 1. The charged antigens showed differences among
strains of serotype 1 similar to those previously reported on the basis of
FA studies (Brock and Georg, 1969; Slack et al., 1969).
A more detailed study of the wall carbohydrate antigens of A. israelii
confirmed the presence of a specific carbohydrate component in A. israelii
serotype 2. Common carbohydrate antigens found in all strains of A.
israelii were not found in other oral Gram-positive rods. A comparison
of stock strains and recent isolates showed the presence of carbohydrate
antigens in fresh isolates of A. israelii serotype 1 which were not present in
the stock strains. The strains could be identified as A. israelii on the basis
of the common antigen. Differences apparently similar to the serotype
differences in A. israelii exist in the carbohydrate antigens of A. naeslundii
and A. viscosus. Cell wall carbohydrate from human A. viscosus has two
components; one was specific for A. viscosus serotype 2 and one was common to A. viscosus serotype 2 and A. naeslundii.
Other studies of the antigenic composition of Actinomyces have been
devoted primarily to A. viscosus. Hammond et al. (1976) demonstrated
several antigens in Rantz and Randall extracts of cell walls of A. viscosus
T14 by immunoelectrophoresis. One of these antigens, which was not
present in extracts from an avirulent mutant of strain T14 was isolated
and characterised. The high molecular weight antigen was composed of
two parts; a polysaccharide with 6-deoxytalose as the major antigenic
component and a small peptide. The virulence associated 6-deoxytalose
containing antigen was found in other strains of A. viscosus and in A.
naeslundii, but not in other Actinomyces species.
More recently, Cisar et al. (1978) showed a quantitative rather than a
qualitative difference in strains T14 V and T14 AV and presented evidence
that the virulence antigen is associated with fibrils present on the cell
surface of A. viscosus. The chemical nature of the virulence associated
antigen on the fibrillar layer is not known, but it is not the 6-deoxytalose
containing antigen described by Hammond et al. (1976).
M. A. GERENCSER
at pH 8.6. They can be detected in acid and autoclave extracts of whole
cells as well as in purified wall preparations.
The charged antigens (group 2) are more complex than the group 1
antigens. The charged antigens were trypsin resistant, pronase sensitive,
and acid and heat stable. Trypsin-treated cell walls seemed to contain both
groups of antigens, but pronase-treated walls contained only the group 1
antigens. Charged antigens from acid extracts were very similar to culture
medium supernate antigens and showed a more complex pattern in
precipitin tests than autoclave extracts.
Fractionation of the wall carbohydrate antigens of A. israelii yielded
two components, one which was serotype 2 specific and one which crossreacted with serotype 1. The charged antigens showed differences among
strains of serotype 1 similar to those previously reported on the basis of
FA studies (Brock and Georg, 1969; Slack et al., 1969).
A more detailed study of the wall carbohydrate antigens of A. israelii
confirmed the presence of a specific carbohydrate component in A. israelii
serotype 2. Common carbohydrate antigens found in all strains of A.
israelii were not found in other oral Gram-positive rods. A comparison
of stock strains and recent isolates showed the presence of carbohydrate
antigens in fresh isolates of A. israelii serotype 1 which were not present in
the stock strains. The strains could be identified as A. israelii on the basis
of the common antigen. Differences apparently similar to the serotype
differences in A. israelii exist in the carbohydrate antigens of A. naeslundii
and A. viscosus. Cell wall carbohydrate from human A. viscosus has two
components; one was specific for A. viscosus serotype 2 and one was common to A. viscosus serotype 2 and A. naeslundii.
Other studies of the antigenic composition of Actinomyces have been
devoted primarily to A. viscosus. Hammond et al. (1976) demonstrated
several antigens in Rantz and Randall extracts of cell walls of A. viscosus
T14 by immunoelectrophoresis. One of these antigens, which was not
present in extracts from an avirulent mutant of strain T14 was isolated
and characterised. The high molecular weight antigen was composed of
two parts; a polysaccharide with 6-deoxytalose as the major antigenic
component and a small peptide. The virulence associated 6-deoxytalose
containing antigen was found in other strains of A. viscosus and in A.
naeslundii, but not in other Actinomyces species.
More recently, Cisar et al. (1978) showed a quantitative rather than a
qualitative difference in strains T14 V and T14 AV and presented evidence
that the virulence antigen is associated with fibrils present on the cell
surface of A. viscosus. The chemical nature of the virulence associated
antigen on the fibrillar layer is not known, but it is not the 6-deoxytalose
containing antigen described by Hammond et al. (1976).