Providencia rettgeri

Providencia rettgeri (commonly P. rettgeri), is a Gram negative bacterium that is commonly found in both water and land environments. "P. rettgeri" is in the genus Providencia, along with "Providencia stuartii", "Providencia alcalifaciens", and "Providencia rustigianii". "P. rettgeri" can be incubated at 37 °C in nutrient agar or nutrient broth. It was first discovered in 1904 after a waterfowl epidemic. Strains of the species have also been isolated from nematodes of the genus "Heterorhabditis".
Identification.
"P. rettgeri" can be identified by its motility and its ability to produce acid from mannitol. It does not produce gas from glucose and does not ferment lactose. It also does not produce hydrogen sulfide or acid from xylose.
Pathogenicity.
"Providencia rettgeri" can cause a number of opportunistic infections in humans and can be found in the human gut. It is a major cause of traveller's diarrhea. Strains of "P. rettgeri" have also been found to cause urinary tract infections and eye infections.
Research in insects.
"Providencia rettgeri" is a natural pathogen of "Drosophila" fruit flies. Susceptibility to "P. rettgeri" is strongly tied to an allele of the antimicrobial peptide gene Diptericin. The fly's defence against "P. rettgeri" seems to rely almost exclusively on Diptericin, as deletion of Diptericin leads to complete mortality. Meanwhile deletion of multiple other antimicrobial peptides has no effect on "P. rettgeri" virulence. Yet defence against the related "Providencia burhodogranariea" is determined by multiple antimicrobial peptides beyond just Diptericin.