Pichia cecembensis sp nov isolated from a papaya fruit (Carica papaya L., Caricaceae)

The ascogenous yeast YS16(T) was isolated from a decaying papaya fruit. Phenotypic traits such as multilateral budding, spheroidal or elongate shape, pseudohyphae formation, asci with one or more ascospores, ability to ferment D-glucose, inability to assimilate nitrate and the presence of Q7 ubiquinone suggest its affiliation to the genus Pichia. The nearest phylogenetic neighbor, based on D1/D2 domain sequence of the 26S rRNA gene and ITS region sequence, was identified as Issatchenkia orientalis (NRRL Y-5396(T), a synonym of Pichia kudriavzevii) with similarities of 98.2% and 97% respectively. In addition to the difference in the D1/D2 and ITS region sequence, YS16(T) differs from I. orientalis with respect to a number of phenotypic traits. However, in the phylogenetic analysis, YS16(T) showed close relatedness to the P. membranifaciens clade. Thus, it is proposed to assign the status of a new species to YS16(T), for which the name P. cecembensis sp. nov. is proposed. The type strain of P. cecembensis sp. nov. is YS16(T) (=NRRL Y-27985(T)=JCM 13873(T)=CBS 10445(T)).