Phylogenomic and biochemical analysis reassesses temperate marine yeast Yarrowia lipolytica NCIM 3590 to be Yarrowia bubula.

Yarrowia clade contains yeast species morphologically, ecologically, physiologically and genetically diverse in nature. Yarrowia lipolytica NCIM 3590 (NCIM 3590), a biotechnologically important strain, isolated from Scottish sea waters was reinvestigated for its phenotypic, biochemical, molecular and genomic properties as it exhibited characteristics unlike Y. lipolytica, namely, absence of extracellular lipolytic activity, growth at lower temperatures (less than 20 °C) and in high salt concentrations (10% NaCl). Molecular identification using ITS and D1/D2 sequences suggested NCIM 3590 to be 100% identical with reference strain Yarrowia bubula CBS 12934 rather than Y. lipolytica CBS 6124 (87% identity) while phylogenetic analysis revealed that it clustered with Y. bubula under a separate clade. Further, whole genome sequencing of NCIM 3590 was performed using Illumina NextSeq technology and the draft reported here. The overall genome relatedness values obtained by dDDH (94.1%), ANIb/ANIm (99.41/99.42%) and OrthoANI (99.47%) indicated proximity between NCIM 3590 and CBS 12934 as compared to the reference strain Y. lipolytica. No extracellular lipase activity could be detected in NCIM 3590 while LIP2 gene TBLASTN analysis suggests a low 42% identity with e value 2 e-77 and 62% coverage. Hence molecular, phylogenetic, genomics, biochemical and microbial analyses suggests it belongs to Yarrowia bubula.