Toxigenic clostridia

Abstract

Toxigenic clostridia belonging to 13 recognized species are discussed in this review. Each species or group of organisms is, in general, introduced by presenting the historical aspects of its discovery by early investigators of human and animal diseases. The diseases caused by each species or group are described and usually discussed in relation to the toxins involved in the pathology. Morphological and physiological characteristics of the organisms are described. Finally, the toxins produced by each organism are listed, with a presentation of their biological activities and physical and biochemical characteristics. The complete amino acid sequences for some are known, and some of the genes have been cloned. The term toxin is used loosely to include the various antigenic protein products of these organisms with biological and serological activities which have served as distinguishing characteristics for differentiation and classification. Some of these factors are not truly toxic and have no known role in pathogenicity. Some of the interesting factors common to more than one species or group are the following: neurotoxins, lethal toxins, lecithinases, oxygen-labile hemolysins, binary toxins, and ADP-ribosyltransferases. Problems in bacterial nomenclature and designation of biologically active factors are noted.

A Novel Anti-Vascular Therapy for Cancer

“…The growth of these bacteria in hypoxic areas of the tumor, presumably killed tumor cells, but could also have caused apoptosis of residual endothelial cells, possibly by induction of tumor necrosis factor alpha (TNF-α), or by other locally active toxins made by C. novyi-NT. 17 In addition to the new mechanisms on anti-microtubule agents provided by this report, and on the synergy of bacteriolytic therapy with these agents, the experiments described by Dang et al 1 have important clinical implications. For certain inoperable bulky tumors such as in the brain, liver or colon, it would be important to avoid rapid necrosis, possibly by decreased dosing of the microtubule regulators spread out over time.…”

Prevalence and molecular typing of Clostridium perfringens isolates from edible offal of broiler

“…The pathogenicity of the organism is associated with several toxins which are also used for toxin typing of the bacteria, within them all strains of the bacterium produce alpha (α) toxin encoded by cpa gene. The other major lethal toxins produced by the organism are beta (β), epsilon (ε) and iota (ι) that are closely related with the virulence of bacteria (16,30). In addition to these major lethal toxins, some strains, with a ratio of 0 to 5 %, have a capability of producing C. perfringens enterotoxin encoded by cpe gene that is the main cause of common C. perfringens type A food poisoning (18,25).…”

“…In addition to these major lethal toxins, some strains, with a ratio of 0 to 5 %, have a capability of producing C. perfringens enterotoxin encoded by cpe gene that is the main cause of common C. perfringens type A food poisoning (18,25). Different types of foods have been involved in the outbreaks of C. perfringens in meat, particularly poultry meat and meat products (5,14,16). As C. perfringens is an ubiquitous pathogen and common intestinal inhabitant of poultry, different stages of poultry production line can be evaluated as a contamination source even starting from the hatchery.…”

Necrotizing enteritis associated with Clostridium perfringensType B in chinchillas (Chinchilla lanigera)

“…When injected i.d. into guinea pigs, a minimum dose of 2 ng causes purple areas of dermatonecrosis (Hatheway 1990). Epsilon toxin is produced as a prototoxin that is activated by proteolytic enzymes produced by the same organism (the kappaand lambda-toxins), or it can be activated by adding trypsin to the culture (Hatheway 1990).…”

“…C. perfringens is classiϐied in ϐive toxinotypes (A-E), according to the production of 4 major toxins (alpha [CPA], beta [CPB], epsilon [ETX], and iota [ITX]) (Hatheway 1990). C. perfringens type B produces alpha, beta and epsilon toxin .…”