Pseudoalteromonas holothuriae sp. nov., isolated from the sea cucumber Holothuria forskali.

Abstract

Two motile bacterial strains, designated as cfHf56-1^T and SW 252, were isolated from the coelomic fluid of Holothuria forskali and from the surrounding seawater at the animal sampling site, respectively. The sea cucumber was collected in the Glénan archipelago (Brittany, France). Strains cfHf56-1^T and SW 252 were Gram-stain-negative, non-spore-forming and rod-shaped bacteria. Colonies made on marine agar plates were brown in color. The pH and temperature ranges for growth were 7-8 and 18-30 °C, respectively, in marine broth. The major fatty acids were 16 : 1 cis9 and 16 : 0. Phylogenetic analyses evidenced that both strains belong to a novel species in the genus Pseudoalteromonas. The strains were closely related to the type strains of Pseudoalteromonas caenipelagi, Pseudoalteromonas byunsanensis and Pseudoalteromonas amylolytica, with 75-78 % ANI and 19-21 % dDDH values. In this context, cfHf56-1^T (= CIP 111854^T = CECT 30642^T) is considered as the type strain of the novel species for which the name Pseudoalteromonas holothuriae sp. nov. is proposed. The genome of the type strain is characterized by a size of 5.1 Mbp and a G+C content of 40.5%.