408
PETER BERNFELD
rence is rare, however (312), and in the intestine of the sea urchin
(313). In sea-water bacteria, 12 out of 200 strains investigated were
found to be alginolytic (these bacteria are termed Alginovibrio), and
9 out of 200 soil bacteria fall into two genera, namely, Alginomonas and
Alginobacter. Alginic acid being a seaweed polysaccharide, Thj0tta and
Käss conclude that it is peculiar to find the most energetic alginase
activity in soil bacteria, rather than in sea-water bacteria.
Studies on the specificity of alginase toward other polyuronides have
not been published. It is known, however, that polymannuronate is not
hydrolyzed by polygalacturonase (305).
C. HEMICELLULASES
Hemicellulose is a variety of plant polysaccharides that are water
insoluble and occur in the cell walls in association with cellulose and
pectic substances. This group of structural polymers comprises a large
number of individual polysaccharides which all contain hexoses, pentoses, and glycuronic acids (295).
Enzymes that solubilize these hemicelluloses have been found in
association with cellulases and pectic enzymes, in particular in the
digestive tracts of the snail and ship worm, in potato sprouts, and in
Aspergillus oryzae (254).
Because of the difficulties in obtaining the substrate in pure form, this
class of enzymes is not well defined and delimited from cellulases, pectic
enzymes, xylanases, etc., i.e., from enzymes which bring about the
biological breakdown of insoluble cell wall material.
X. Enzymes That Hydrolyze Pneumococcal Polysaccharides
Among the large number of heteropolysaccharides known, only a
few have been reported to possess specific enzymes that catalyze their
degradation.
Pneumococcus polysaccharide type III, which consists of D-glucose
and D-glucuronic acid in a 1:1 ratio, is hydrolyzed by an enzyme
obtained from filtered autolyzates of cultures of a saprophytic bacillus
(314).
In spite of the chemical similarity between the pneumococcus polysaccharides type III and type VIII, the latter containing D-glucose and
D-glucuronic acid in a 7:2 ratio, and in spite of the immunological
analogy between the two polysaccharides of producing cross reactions,
the enzyme action is limited to the type III polysaccharide, a rather remarkable phenomenon of enzymatic specificity.
The role of this enzyme to protect against pneumococcal infection
PETER BERNFELD
rence is rare, however (312), and in the intestine of the sea urchin
(313). In sea-water bacteria, 12 out of 200 strains investigated were
found to be alginolytic (these bacteria are termed Alginovibrio), and
9 out of 200 soil bacteria fall into two genera, namely, Alginomonas and
Alginobacter. Alginic acid being a seaweed polysaccharide, Thj0tta and
Käss conclude that it is peculiar to find the most energetic alginase
activity in soil bacteria, rather than in sea-water bacteria.
Studies on the specificity of alginase toward other polyuronides have
not been published. It is known, however, that polymannuronate is not
hydrolyzed by polygalacturonase (305).
C. HEMICELLULASES
Hemicellulose is a variety of plant polysaccharides that are water
insoluble and occur in the cell walls in association with cellulose and
pectic substances. This group of structural polymers comprises a large
number of individual polysaccharides which all contain hexoses, pentoses, and glycuronic acids (295).
Enzymes that solubilize these hemicelluloses have been found in
association with cellulases and pectic enzymes, in particular in the
digestive tracts of the snail and ship worm, in potato sprouts, and in
Aspergillus oryzae (254).
Because of the difficulties in obtaining the substrate in pure form, this
class of enzymes is not well defined and delimited from cellulases, pectic
enzymes, xylanases, etc., i.e., from enzymes which bring about the
biological breakdown of insoluble cell wall material.
X. Enzymes That Hydrolyze Pneumococcal Polysaccharides
Among the large number of heteropolysaccharides known, only a
few have been reported to possess specific enzymes that catalyze their
degradation.
Pneumococcus polysaccharide type III, which consists of D-glucose
and D-glucuronic acid in a 1:1 ratio, is hydrolyzed by an enzyme
obtained from filtered autolyzates of cultures of a saprophytic bacillus
(314).
In spite of the chemical similarity between the pneumococcus polysaccharides type III and type VIII, the latter containing D-glucose and
D-glucuronic acid in a 7:2 ratio, and in spite of the immunological
analogy between the two polysaccharides of producing cross reactions,
the enzyme action is limited to the type III polysaccharide, a rather remarkable phenomenon of enzymatic specificity.
The role of this enzyme to protect against pneumococcal infection