"Serratia" secrete a host of virulence factors including prodigiosin, biosurfactants, DNAse, lipase, protease, gelatinase, hemolysin, chitinase, chloroperoxidase, and alkaline phosphatase. Prodigiosin, a growth pigment, is often used as a phenotypic identification marker of "Serratia" species due to its red colorization. Biosurfactants have been isolated from "Serratia" "marcescens," "Serratia rubidaea" and "Serratia surfactantfaciens" for their range of applications including emulsification, surface, antifouling, antitumor, and antimicrobial activity. Endonucleases, such as DNAse, may aid in scavenging activity, allowing them to exploit the environment and maximize availability of nutrients. Strains producing thermostable lipase, alkaline protease and gelatinase have been isolated from strains causing contact lens-related corneal ulcers in humans. Due to its short half-life and tendency to remain bound to cells upon secretion, hemolysin has scarcely been identified in "Serratia." However, some studies employing more accurate detection techniques have evidenced hemolytic activity in almost all strains of "Serratia". Plant chitinases are used as defense mechanisms against plant pathogens with which "Serratia" shares their plant habitat. Chloroperoxidase allows hydrolysis of phosphodiester bonds while alkaline phosphatases are involved in cell signaling processes.