Transfer of Pectobacterium carotovorum subsp. carotovorum strains isolated from potatoes grown at high altitudes to Pectobacterium peruviense sp. nov.

Abstract

Seven Gram-negative, rod-shaped pectinolytic bacteria strains designated as IFB5227, IFB5228, IFB5229, IFB5230, IFB5231, IFB5232, IFB5636, isolated from potato tubers cultivated in Peru at high altitude (2400–3800m) were subjected to polyphasic analyses that revealed their distinctiveness from the other Pectobacterium species. Phylogenetic analyses based on five housekeeping genes (gyrA, recA, recN, rpoA and rpoS) clearly showed strains separateness, simultaneously indicating Pectobacterium atrosepticum, Pectobacterium wasabiae, Pectobacterium parmentieri and Pectobacterium betavasculorum as the closest relatives. In silico DNA–DNA hybridization of strain IFB5232T with other Pectobacterium type strains revealed significant drop in DDH value below 70%, which is a prerequisite to distinguish Pectobacterium peruviense. The ANI values supported the proposition of delineation of the P. peruviense. Genetic REP-PCR fingerprint and detailed MALDI-TOF MS proteomic profile sealed the individuality of the studied strains. However, phenotypic assays do not indicate immense differences.Provided results of analyses performed for seven Peruvian strains are the basis for novel species distinction and reclassification of the strains IFB5227-5232 and IFB5636, previously classified as Pectobacterium carotovorum subsp. carotovorum. Here, we propose to establish the IFB5232 isolate as a type strain (=PCM2893T=LMG30269T=SCRI179T) with the name Pectobacterium peruviense sp. nov.