Marinomonas piezotolerans sp. nov., isolated from deep-sea sediment of the Yap Trench, Pacific Ocean

A Gram-stain-negative, aerobic and rod-shaped strain, YLB-(T), was isolated from a sample of deep-sea sediment (depth, 6796 m) from the Yap Trench. It was motile, oxidase-positive and catalase-positive. Growth was observed at salinities of 1-12 % (NaCl, w/v), with the optimum at 5 %. The strain was able to thrive at low (4 degrees C) temperatures, with the optimum at 37 degrees C, but did not grow at 50 degrees C. The optimum pressure for growth was 0.1 MPa with tolerance up to 50 MPa. The 16S rRNA gene sequencing analysis showed that YLB-05(T) was most closely related to Marinomonas communis LMG 2864(T) (97.8 %). Phylogenetic analysis placed strain YLB-05(T )within the genus Marinomonas. The average nucleotide identity and the DNA-DNA hybridization values between strain YLB-05(T) and closely related type strains were below the respective thresholds for species differentiation. The principal fatty acids were C-16(:0), summed feature 8 (C-18(:1)omega 7c and/or C-18:(1)omega 6c) and summed feature 3 (C-16:1 omega 7c/(C16:)(1)omega 6c). The DNA G+C content was 45.7 mol%. The respiratory quinone was determined to be Q-8. The polar lipids were an unidentified phospholipid and an unidentified aminophospholipid. The combined genotypic and phenotypic data showed that strain YLB-05(T) represents a novel species within the genus Marinomonas, for which the name Marinomonas piezotolerans sp. nov. is proposed, with the type strain YLB-05(T) (=MCCC 1A12712(T) =KCTC 62812(T)).