Citrobacter freundii strain NCTC13639

Citrobacter freundii strain NCTC13639 is a Gram-negative, rod-shaped bacterium that thrives in various habitats, including hospital sewage, the intestinal tract, sewage, soil, and surface waters. It is classified as a facultative anaerobe, indicating its ability to grow in both aerobic and anaerobic environments, and possesses true flagella, which facilitate its motility. This strain has a single replicon and is known to infect a diverse array of hosts, including humans (Homo sapiens), various animals such as rabbits (Oryctolagus cuniculus), tilapia, domestic dogs (Canis lupus familiaris), and cats (Felis catus), as well as amphibians and fish. The bacterium is recognized for being an opportunistic pathogen, responsible for infections in humans and animals, particularly affecting the urinary and respiratory tracts. In horses, it can lead to respiratory tract and wound infections, while in dogs and cats, it is associated with respiratory tract infections and pleuritis. C. freundii strain NCTC13639 is nonsporulating, which may influence its ecological persistence and pathogenicity. The wide range of hosts and environments it occupies suggests a significant role in both clinical settings and natural ecosystems. The bacterium's presence in hospital sewage underlines its relevance in healthcare, where it can pose infection risks, particularly in immunocompromised patients. Understanding its ecological niche and pathogenic potential is essential for managing infections and preventing outbreaks in both humans and animals.