pseudomonas fragi pseudomonas fragi pseudomonas fragi is a psychrophilic, gram-negative bacterium that is responsible for dairy spoilage. unlike many other members of the genus pseudomonas, p. fragi does not produce siderophores. optimal temperature for growth is 30 °c, however it can grow between 0 and 35 °c. based on 16s rrna analysis, p. fragi has been placed in the p. chlororaphis group. pseudomonas fragi scientific classification domain: bacteria phylum: pseudomonadota class: gammaproteobacteria order: pseudomonadales family: pseudomonadaceae genus: pseudomonas species: p. fragi binomial name pseudomonas fragi(eichholz 1902) gruber 1905 type strain atcc 4973 ccug 556 cfbp 4556 cip 55.4 dsm 3456 hambi 28 lmg 2191 nbrc 3458 nccb 69033 nctc 10689 nrrl b-25 and b-727 vkm b-898 synonyms bacterium fragi eichholz 1902