Journal of Life Sciences 11 (2017) 11-18 doi: 10.17265/1934-7391/2017.01.002 Metabolomics Study in Methylotrophic Yeast: A Minireview Jye Ping Fam 1, 2 , Suriana Sabri 1, 3 , Syarul Nataqain Baharum 4 , Abu Bakar Salleh 1, 2 and Siti Nurbaya Oslan 1, 2 1. Enzyme and Microbial Technology Research Centre, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia 2. Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia 3. Department of Microbiology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia 4. Institute of Systems Biology, Universiti Kebangsaan Malaysia, Bangi 43600, Selangor, Malaysia Abstract: Methylotrophic yeast has been used as a cost-effective and valuable host for expression of recombinant protein due to its unique methanol utilisation pathway. It has an AOX (alcohol oxidase) protein which has been characterised to be a strong and tightly methanol-inducible dependent promoter. Metabolomics is the systematic study and inclusive analysis of small molecules called metabolites in a biological system. Metabolomics plays an important part in connecting the phenotype and genotype gap because it magnifies the modifications in the proteome and provides a better phenotype representation of an organism. This quantitative study has provided a new perception on the metabolic burden derived from the overexpression of recombinant protein in methylotrophic yeast. In this review, we discuss the fundamental aspect of metabolomics in methylotrophic yeast followed by their latest developments. Key words: Methylotrophic yeast, metabolomics, methanol utilisation pathway. 1. Introduction Methylotrophic yeast has been recognised as a cost-effective and valuable host for production of a wide range of heterologous proteins. It has advantages over prokaryotic expression systems, for example, ease in handling and cultivation, cheap and simple media requirements. It is comparable to mammalian cells, and the capability to perform essential eukaryotic post-translational modification thus producing functional recombinant proteins [1]. Metabolomics is the inclusive and quantitative appraisal of endogenous metabolites and challenges to methodically distinguish and quantify metabolites from biological samples. Due to the fast turnover of intracellular metabolites, it is essential to have dependable and reproducible procedures and techniques for sampling and sample treatment. Sampling Corresponding author: Siti Nurbaya Oslan, Ph.D., research fields: microbial biotechnology, bioinformatics. metabolites is a significant issue, particularly for planktonic cells, as the sampling process may disturb metabolic system [2]. There are a few techniques broadly used for extracting metabolites from yeast cells, for instance, freeze-thaw, sonication, hot water, boiling ethanol, permeabilization utilizing chloroform and treatment with outrageous pH [3]. However, a universal sample preparation protocol does not exist. Recently, studies were carried out to develop a better protocol to extract metabolites from yeasts cells through different kinds of methods [2, 4-6]. 2. Methylotrophic Yeast Methylotrophs are microorganisms that have the ability to utilise all carbon sources including the 1-carbon (C 1 -) compound. Methylotrophs have a number of metabolic pathways for assimilating and dissimilating C 1 - compound [7]. Prokaryotic methylotrophs are able to utilise a range of C 1 - compounds such as methanol, methylamine and D DAVID PUBLISHING