They are positive for glucose and sucrose (with gas production) fermentation and nitrate test; and negative for indole, urease and oxidase.
Rare reports have described disease resulting from infection with Serratia plymuthica, Serratia liquefaciens, Serratia rubidaea, Serratia odorifera, and Serratia fonticola.
Serratia species are found in faeces, wound exudates, respiratory specimen, blood, eye culture, and urine20.
Serratia marcescens is the type species