Characterization and Diagnostics of Listeria Monocytogenes: A Human Pathogen

Abstract

Listeria monocytogenes, Gram positive bacteria, rod-shaped, intracellular, opportunistic, invasive food borne bacterium, which is ubiquitous in nature. Soil, vegetation, sewage, water, and fecal materials are its primary source through which it reaches to our food system. It is one of the leading food borne bacteria which is pathogenic, causing Listeriosis in immunodeficient children, adult, pregnant women, central nervous system infection, bacteremia, and other clinical manifestation. Bacterium has arsenal of virulence factors Listeriolysin, phospholipases, internalins and Act A protein which help to enter, invade and infect the host cell, escape from autophagy and promote cell to cell spread. It can withstand diverse environmental parameters, that is, low temperatures, pH, osmotic and oxidative stress. Bacterium is deadly to humans and is food borne, causing economic losses and is a threat to food industry. Present review gives an overview of bacterial characteristics, etiology, isolation, distribution and pathogenicity of L. monocytogenes.