Mannheimia glucosida


Mannheimia glucosida is a species of Gram-negative bacteria in the family Pasteurellaceae. It was first described in 1999 following a taxonomic revision of the Pasteurella haemolytica complex.

Etymology

The species name glucosida is derived from the Greek word glykys meaning "sweet" and the Latin suffix -ida, indicating a connection to glucosides. The name reflects the bacterium's ability to ferment glucoside sugars.

Morphology and physiology

M. glucosida is a non-motile, Gram-negative coccobacillus. It is facultatively anaerobic and forms small, grayish, smooth colonies on blood agar, often exhibiting β-hemolysis. The bacterium grows optimally at 37°C and can ferment glucose, lactose, maltose, and sucrose without gas production. It is oxidase-positive and catalase-positive.

Isolation and habitat

The type strain was isolated from the lung of a sheep. Other strains have been recovered from the upper respiratory tracts of healthy ruminants, especially sheep and cattle, indicating a role as part of the commensal microbiota.

Clinical significance

M. glucosida has been implicated in ovine mastitis. A 2010 study in southeastern Australia found it in 50% of clinical mastitis cases, while it was rarely found in healthy udder samples.
Although primarily a veterinary organism, M. glucosida has also been isolated from a human bite wound, suggesting its potential as a zoonotic pathogen.

Molecular identification

Molecular diagnostic methods such as PCR and 16S rRNA gene sequencing are used to identify M. glucosida. A 2015 study validated a multiplex PCR assay that differentiates among closely related Pasteurellaceae species, including M. glucosida, based on capsule loci and other genetic markers.