Raoultella

Members of genus Raoultella grow at 10 °C consistent with their recovery from plants, soil, and water, whereas members of Klebsiella do not grow at 10 °C^[5] and are mainly recovered from mammals' mucosae. Klebsiella oxytoca is an exception, and a proposal to classify K. oxytoca in a separate, unnamed genus has been made.^[6]

It consists of species Raoultella electrica, Raoultella ornithinolytica, Raoultella planticola and Raoultella terrigena.^[7]

In human infections, Raoultella species are generally sensitive to treatment with carbapenems. In one series, 92% were sensitive to ciprofloxacin. More than 10% produced extended-spectrum beta-lactamases.^[8]

Type species for this genus are:

• Raoultella electrica 1GB^T[9][10]
• Raoultella ornithinolytica ATCC 31898^T[1][11]
• Raoultella planticola ATCC 33531^T[1][12]
• Raoultella terrigena ATCC 33257^T[1][13]

A phylogenetic tree of Klebsiella, based on a 2.93-Mbp alignment, unambiguously places R. ornithinolytica sister to K. oxytoca within the larger Klebsiella phylogeny and suggests abandoning the genus Raoultella designation.^[14]

Robust phylogenetic analyses have repeatedly shown that species classified into this genus are nested in the genus Klebsiella, indicating Raoultella should be abandoned and considered a junior synonym of Klebsiella.^{[15][16][17][18]}

In November 2021, the synonym Klebsiella electrica is reported "not validly published".^[19] The correct name with a valid nomenclatural status is Raoultella electrica.^[10]