During a study of 'tunta' (frozen-dry potato) production process in Peru a strain named LMT03T was isolated from the grasses straw in which the potato are dried. This strain was classified into genus Pseudomonas on the basis of the 16S rRNA gene sequence analysis, and the closest related species is Pseudomonas argentinensis CH01T with 99.3% identity in this gene and 96%, 92% and 86% identities in rpoB, rpoD and gyrB genes, respectively. The strain shows a polar single flagellum, like other related yellow pigment producing pseudomonads. The major quinone was Q9. The major fatty acids were 18:1 ω7c in summed 8 (40.82%), 16:1 ω6c/ 16:1 ω6c in summed feature 3 (23.72%) and C16:0 (15.20%). The strain produces oxidase but it does not produce gelatinase, indole, urease, arginine dihidrolase or β-galactosidase. Catalase production was very weak after 28 and 48h incubation on nutrient agar medium. Nitrate reduction was negative. It does not hydrolyse aesculin. The G+C DNA content was 57.8 mol %. DNA-DNA hybridization results showed lower than 52% relatedness with respect to the type strain of Pseudomonas argentinensis CH01T. These results together with other phenotypic characteristics support the definition of a new species within genus Pseudomonas, for which the name P. punonensis sp. nov. is proposed. The type strain is LMT03T = M4PAPS15 T (LMG 26839T, CECT 8089T).

This research was granted by Projects PROCOM 255-2008-CONCYTEC-OAJ and 223 PROCOM 273-2009-CONCYTEC-OAJ (Lima, Peru) as well as Junta de Castilla y 224 León (Regional Spanish Government). MHRB is recipient of a JAE-Doc researcher 225 contract from CSIC

17 páginas, 2 tablas, 1 figura.-- The definitive versión is available at http://www.sgm.ac.uk/

Peer reviewed