Strains have all the characteristics of members of the family Enterobacteriaceae. Cells are Gram-negative rods, measuring 0.9×1.5–3.0 µm, and occur as single and pairs. Cells are motile and non-spore-forming. After growth for 24–48 h on nutrient agar at 27±1 °C, colonies are light beige, circular (1–1.2 mm in diameter) and convex and with entire margins. Does not produce fluorescent pigment on King’s medium B. Growth in yeast salt and liquid 523 medium (Schaad et al., 2001) occurs at 36 °C, but not at 39 °C. Able to grow in 5 % (w/v) NaCl. Facultatively anaerobic. Oxidase is not produced. Results obtained with API20E tests (bioMérieux) give a positive result for β-galactosidase activity, but a negative result for activities of arginine dihydrolase, lysine decarboxylase, ornithine decarboxylase, urease, tryptophan deaminase, phenylalanine deaminase and gelatinase (except strain DAPP-PG 672). Citrate is not utilized; hydrogen sulfide, indole and acetoin (except strains CECT 5262 and CECT 5264) are not produced. Nitrate is reduced to nitrite. Results obtained with API 50CHE tests (bioMérieux) indicate that strains utilize the following substrates as sole carbon sources at 27±1 °C within 2 days: l-arabinose, d-ribose, d-galactose, d-glucose, d-fructose, d-mannose, l-rhamnose, d-mannitol, N-acetylglucosamine, aesculin, trehalose, d-arabitol, potassium gluconate and potassium 2-ketogluconate, and arbutin and salicin (except strains DAPP-PG 531T and DAPP-PG 537). The following carbon sources are not utilized at 27±1 °C within 2 days: glycerol, erythritol, d-arabinose, d-xylose, l-xylose, d-adonitol, methyl β-d-xylopyranoside, l-sorbose, dulcitol, inositol, d-sorbitol, methyl α-d-mannopyranoside, methyl α-d-glucopyranoside, amygdalin, cellobiose, maltose, lactose, melibiose, sucrose, inulin, melezitose, raffinose, starch, glycogen, xylitol, gentiobiose, turanose, d-lyxose, d-tagatose, d-fucose, l-fucose, l-arabitol and potassium 5-ketogluconate. The DNA G+C content of the five strains ranges from 54.7 to 54.9 mol% as determined by the method of Mesbah et al. (1989).

The type strain, DAPP-PG 531T ( = LMG 25322T = DSM 23398T) and DAPP-PG 537 ( = LMG 25323 = DSM 23412), were isolated in Umbria (Italy) from olive knots caused by Pseudomonas savastanoi pv. savastanoi. Additional strains were isolated in Apulia (Italy) (DAPP-PG 672 = LMG 25321 = DSM 23411) and Spain (CECT 5262 = LMG 25327, CECT 5264 = LMG 25328) also from olive knots caused by Pseudomonas savastanoi pv. savastanoi.