Abstract
Strain P-2P44(T) was isolated from creosote-contaminated marine sediments by using a most-probable number procedure in which phenanthrene was the sole carbon and energy source. Growth experiments showed that P-2P44(T) utilized several two- and three-ring polycyclic aromatic hydrocarbons (PAHs) as substrates, including naphthalene, 2-methylnaphthalene and phenanthrene. Additionally, gas-chromatography experiments showed that P-2P44(T) degraded several other PAHs, though it was unable to use them as sole sources of carbon and energy. Phylogenetic analyses confirmed that strain P-2P44(T) is a member of the genus Vibrio, most closely related to Vibrio splendidus. However, strain P-2P44(T) shared only 98.3% 16S rDNA identity and 35% DNA--DNA reassociation with the type strain of V. splendidus. Strain P-2P44(T) differed phenotypically from V. splendidus. Together, these differences indicated that strain P-2P44(T) represents a novel species in the genus Vibrio, for which the name Vibrio cyclotrophicus sp. nov. is proposed; the type strain is P-2P44(T) (=ATCC 700982(T)=PICC 106644(T)).