Pseudomonas cerasi sp. nov. (non Griffin, 1911) isolated from diseased tissue of cherry

Eight isolates of Gram-negative fluorescent bacteria (58T, 122, 374, 791, 963, 966, 970a and 1021) were obtained from diseased tissue of cherry trees from different regions of Poland. The symptoms resembled those of bacterial canker. Based on an analysis of 16S rDNA sequences the isolates shared the highest over 99.9% similarity with Pseudomonas ficuserectae JCM 2400T and P. congelans DSM 14939T. Phylogenetic analysis using housekeeping genes gyrB, rpoD and rpoB revealed that they form a separate cluster and confirmed their closest relation to P. syringae NCPPB 281T and P. congelans LMG 21466T. DNA–DNA hybridization between the cherry isolate 58T and the type strains of these two closely related species revealed relatedness values of 58.2% and 41.9%, respectively. This was further supported by Average Nucleotide Identity (ANIb) and Genome-to-Genome Distance (GGDC) between the whole genome sequences of strain LMG 28609T and closely related Pseudomonas species. The major cellular fatty acids are 16:0 and summed feature 3 (16:1 ω7c/15:0 iso 2OH). Phenotypic characteristics differentiated the novel isolates from other closely related species. The G+C content of the genomic DNA of strain 58T was 59%. The diversity was proved by PCR MP and BOX PCR, eliminating the possibility that they constitute a clonal population. Based on the evidence of this polyphasic taxonomic study the eight strains are considered to represent a novel species of the genus Pseudomonas for which the name P. cerasi sp. nov. (non Griffin, 1911) is proposed. The type strain of this species is 58T (=LMG 28609T = CFBP 8305T).