Paul et al. (2021)[3] isolated, characterized and identified salt tolerant Providencia rettgeri from marine sponge (Niphates erecta) of the Saint Martin's Island Area of the Bay of Bengal, Bangladesh.

Colony, morphological, physiological, and biochemical characteristics of Providencia rettgeri are shown in the Table below.

[3] Note: + = Positive, – =Negative P. rettgeri can be identified by its motility and its ability to produce acid from mannitol.

Susceptibility to P. rettgeri is strongly tied to an allele of the antimicrobial peptide gene Diptericin.

Yet defence against the related Providencia burhodogranariea is determined by multiple antimicrobial peptides beyond just Diptericin.