– Clostridium perfringens / C. perfringens (formerly known as C. welchii) is a Gram-positive, rod-shaped, anaerobic, spore-forming bacterium of the genus Clostridium. C. perfringens is ubiquitous in nature and can be found as a normal component of decaying vegetation, marine sediment, the intestinal tract of humans and other vertebrates, insects, and soil. C. perfringens is commonly encountered in infections as a benign component of the normal flora. In this case, its role in disease is minor. Infections due to C. perfringens show evidence of tissue necrosis, bacteremia, emphysematous cholecystitis, and gas gangrene, which is also known as clostridial myonecrosis. NA, also called sialidases, specifically catalyze the hydrolysis removal of terminal sialic acid residues from viral and cellular glycoconjugates. C. Perfringens neuraminidase catalyzes the hydrolysis of alpha-(2->3)-, alpha-(2->6)-, glycosidic linkages of terminal sialic acid residues in oligosaccharides, glycoproteins, glycolipids, colominic acid and synthetic substrates, but has little activity against the α2-8 glycosidic linkages. The function of the neuraminidase is to release sialic acids for use as carbon and energy sources for the non-pathogenic bacterium, while in pathogenic microorganisms, sialidases have been suggested to be pathogenic factors