Description of Anaerococcus kampingiae sp. nov., Anaerococcus groningensis sp. nov., Anaerococcus martiniensis sp. nov., and Anaerococcus cruorum sp. nov., isolated from human clinical specimens

Objectives: To improve the identification of anaerobic bacteria, the identity of clinical isolates which could not be identified using MALDI-TOF MS was assessed using whole genome sequencing (WGS) and in-house made main spectral profiles (MSPs) were created. Four novel Anaerococcus species, each represented by at least two isolates, were encountered.

Methods: The novelty of the isolates was confirmed by comparing the 16S rRNA gene sequences and the WGS with their closest relatives. Phylogenetic and phylogenomic relationships were determined using MEGA X and DSMZ TYGS. Biochemical features were determined and the clustering of the created MSPs was calculated. Possible clinical relevance was assessed.

Results: The novelty of the four different species was confirmed by the ANI value, and phylogenetic/phylogenomic clustering. Three of these species shared the same biochemical features, while one showed a different pattern. Only this latter species can be differentiated from other Anaerococcus spp. Remarkebly, six of the ten isolates were obtained from a positive blood culture, of which in five cases the bacterium was the only species encountered.

Conclusions: We propose to name these novel species: Anaerococcus kampingiae (ENR0874^T = DSM 117234^T, CCUG 77487^T (accession numbers PP192775/JBGMEF000000000)), Anaerococcus groningensis (ENR1011^T = DSM 117232^T, CCUG 77488^T (accession numbers PP192777/JBGMEG000000000)), Anaerococcus martiniensis (ENR0831^T = DSM 117233^T, CCUG 77486^T (accession numbers PP192776/JBGMEI000000000)), and Anaerococcus cruorum (ENR1039^T = DSM 117235^T, CCUG 77489^T (accession numbers PP192778/JBGMEH000000000)).