Strains and approaches for genetic crosses in the oleaginous yeast Lipomyces starkeyi

The oleaginous yeast Lipomyces starkeyi can accumulate intracellular lipids to over 60% of its cell dry mass under a nitrogen-limited condition. We showed that extracellular and intracellular citrate concentrations of L. starkeyi AS 2.1560 increased and the nicotinamide adenine dinucleotide – isocitrate dehydrogenase (NAD+–IDH) activity decreased at the beginning of the lipid accumulation, suggesting that the attenuation of the NAD+–IDH activity might initiate lipid storage. We next cloned the IDH gene by the methods of degenerate PCR and rapid amplification of cDNA ends. Phylogenetic analyses of the evolutionary relationships among LsIDH1, LsIDH2, and other yeast NAD+–IDHs revealed that the L. starkeyi IDH had a closer relationship with the IDHs of Yarrowia lipolytica . Further real-time PCR analysis showed that the expression levels of both LsIDH1 and LsIDH2 decreased concurrently with the evolution of cellular lipids. Our data should be valuable for understanding the biology of oleaginous yeasts and for further strain engineering of L. starkeyi.

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Expression and secretion of fungal endoglucanase II and chimeric cellobiohydrolase I in the oleaginous yeast Lipomyces starkeyi

Microbial Cell Factories ◽

10.1186/s12934-017-0742-5 ◽

2017 ◽

Vol 16 (1) ◽

Cited By ~ 8

Author(s):

Qi Xu ◽

Eric P. Knoshaug ◽

Wei Wang ◽

Markus Alahuhta ◽

John O. Baker ◽

...

Keyword(s):

Oleaginous Yeast ◽

Lipomyces Starkeyi ◽

Cellobiohydrolase I ◽

Endoglucanase Ii

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Establishing CRISPR/Cas9 in Lipomyces starkeyi

Alberta Academic Review ◽

10.29173/aar61 ◽

2019 ◽

Vol 2 (2) ◽

pp. 51-52

Author(s):

Zoe Lau ◽

David Stuart ◽

Bonnie Mcneil

Keyword(s):

Protein Expression ◽

Genome Editing ◽

Oleaginous Yeast ◽

Lipomyces Starkeyi ◽

Guide Rna ◽

Intracellular Lipids ◽

Dry Cell Weight ◽

Cas9 Protein ◽

High Concentrations ◽

Dry Cell

The goal of this project was to adapt the Yarrowia lipolytica plasmid based CRISPR/Cas9 system for usage in Lipomyces starkeyi. Lipomyces starkeyi is an oleaginous yeast, which synthesizes and stores high amounts of intracellular lipids. This specific yeast can store lipids at concentrations higher than 60% of its dry cell weight. Due to these high concentrations of lipids, L. starkeyi is a desired organism for the production of biofuels and other oleochemicals. However, there is a lack of knowledge and of genetic tools when trying to engineer the cells to produce these lipids for our use. The genome editing tool, CRISPR/Cas9 is efficient and simple, therefore desirable for the engineering of L. starkeyi. The goal was achieved by replacing the Y. lipolytica promoter with a L. starkeyi promoter, inserting guide RNA, as well as confirming cas9 protein expression.

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