The relationship of the haemagglutinin of Clostridium welchii to the neuraminidase and other soluble products of the organism

Relationship between hemagglutinin and sialidase from Clostridium perfringens CN3870: chromatographic characterization of the biologically active proteins

Biochemical characterization of hemagglutinin and sialidase activities from Clostridium perfringens strain CN3870 revealed that this strain produced three sialidase enzymes that were separable to gel filtration, ion exchange chromatography, and polyacrylamide gel electrophoresis. The molecular weights of sialidase I, II, and III activities were 310,000 +/- 10,000, 105,000 +/- 4,000 and 64,000 +/- 2,000, respectively, the first figure being an approximate value only.

Relationship between hemagglutinin and sialidase from Clostridium perfringens CN3870: gel filtration of mutant and reverant activities

Gel filtration of supernatant fluids, from the wild-type Clostridium perfringens, strain CN3870, and several of the mutants and reverants derived from this strain, showed that these mutants failed to product detectable amounts of still produced sialidase III activity. The reverants tested had regained the ability to produce approximately wild-type levels of the I and II forms of both activities. These results showthat there is a direct relationship between the production of the I form and hemagglutinin and sialidase activities and the production of the II form of these biologically active proteins. Models that explain the genetic basis for these results are discussed.

Isolation and characterization of Clostridium perfringens mutants altered in both hemagglutinin and sialidase production

The relationship between the production of hemagglutinin and sialidase activities by Clostridium perfringens was investigated by screening for mutants producing reduced levels of hemagglutinin activity. Twelve mutants were isolated; all produced reduced levels of sialidase activity and several had other altered phenotypic markers. Revertants that regained the ability to produce active hemagglutinin were isolated. All of these revertants produced increased sialidase activity. These results show that the production of hemagglutinin activity is directly related to the production of sialidase activity. Evidence is also presented that the processes of sporulation and the production of extracellular proteins are interrelated.

Extracellular proteins in five clostridial species from human infections

347 strains from human infections were identified by gas-liquid chromatography of metabolic products and by conventional tests. Simple agar-plate assays were used to analyze the ability to form extracellular proteins. More than 90% of all strains were hemolytic on agar containing rabbit erythrocytes and all were gelatinase producers. All strains of C. bifermantans, C. sordelli, and C. sporogenes were also caseinolytic on skimmed-milk agar, but strains of C. perfringens, C. novyi types A and B were not. Less than 10% of C. perfringens strains were producers of elastase and staphylolytic enzyme and all other species were non-producers. All C. perfringens, C. novyii, C. bifermentans, and C. sordelli were lecithinase producers, but C. sporogenes was not. All strains of C. sporogenes formed deoxyribonuclease, while a varying number of the other species showed a positive reaction.

Distribution of neuraminidase among food-poisoning strains of Clostridium perfringens

A survey was made to determine the distribution of the enzyme neuraminidase among 76 strains of Clostridium perfringens. Representative strains from each toxigenic type (A to F) and atypical C. perfringens type A food-poisoning strains of both American and English (Hobbs types) origin were tested. Both the American food-poisoning and nonfood-poisoning associated cultures consisted of both neuraminidase-positive and -negative strains. Furthermore, American strains which could not be differentiated from the original Hobbs cultures consisted of both neuraminidase-positive and -negative representatives. In contrast, the English (Hobbs) strains uniformly failed to produce an active intracellular or extracellular neuraminidase. No enzyme activity was detected in these strains when cultures were grown in different growth media, when grown in the presence of substrate (neuraminlactose), or upon extended incubation of enzyme preparations with substrate. With the exception of a type F strain, representative strains of the other toxigenic types (A to F) produced neuraminidase; 85% of the typical type A strains contained the enzyme.