rothia kristinae rothia kristinae rothia kristinae is a gram positive bacterium. r. kristinae is a common human skin organism, but can cause opportunistic infections in humans. rothia kristinae scientific classification domain: bacteria phylum: actinomycetota class: actinomycetia order: micrococcales family: micrococcaceae genus: rothia species: r. kristinae binomial name rothia kristinae(kloos et al. 1974) nouioui et al. 2018 type strain atcc 27570ccm 2690ccug 33026cip 81.69dsm 20032iegm 390ifo 15354jcm 7237lmg 14215nbrc 15354nctc 11038nrrl b-14835vkm b-1811 synonyms micrococcus kristinae kloos et al. 1974 (approved lists 1980) kocuria kristinae (kloos et al. 1974) stackebrandt et al. 1995 background in 1974, a novel bacterium was isolated from the skin of a healthy adult woman. the novel species was originally named micrococcus kristinae, and was named after the person from which it was first isolated (kristin holding). (micrococcus lylae was also first isolated during the same study) in 1995, the species was reclassified into the genus kocuria as kocuria kristinae. in 2018, further studies reclassified the species into genus rothia as rothia kristinae. r. kristinae is gram-positive, and the cells are coccoid which tend to group together as tetrads. it is slightly facultatively anaerobic, and forms pale cream to pale orange colonies when grown on agar. the optimum growth range is 25–37 °c, and is resistant to lysozyme. r. kristinae is a common skin and oral microorganism in humans. however, it can cause opportunistic infections for the immunocompromised.