Histidine is essential for growth of Komagataella phaffii cultured in YPA medium

Abstract

Komagataella phaffii (a.k.a. Pichia pastoris) requires histidine for optimal growth when cultured in a medium containing yeast extract, peptone (YP), and acetate (YPA). We demonstrate that HIS4‐deficient, K. phaffii strain GS115 exhibits a growth defect on YP‐media containing acetate, but not on other carbon sources. K. phaffii X33, a prototroph, grows better than K. phaffii GS115 (his4), a histidine auxotroph in YPA. Normal growth of GS115 is restored either by the expression of HIS4 or by culturing in YPA containing ≥0.6 mM histidine. In the presence of histidine, expression of several genes is altered, including those encoding key subunits of mitochondrial ATP synthase, transporters of amino acids and nutrients, as well as biosynthetic enzymes. Thus, histidine should be included as an essential component for optimal growth of K. phaffii histidine auxotrophs cultured in YPA.

Coordinate regulation of methanol utilization pathway genes of Komagataella phaffii by transcription factors and chromatin modifiers

“…Yeast transformations were performed by electroporation (Gene Pulsar, Bio-Rad). Yeast extract and peptone were procured from the same vendors as mentioned previously ( Gupta and Rangarajan, 2022 ).…”

Alternative PCR-Based Approaches for Generation of Komagataella phaffii Strains

“…For example, auxotrophic markers allow for the selection of yeast transformants on simple minimal media, but they require the corresponding auxotrophic strains. The growth of such strains may be impaired by mutations in the corresponding genes [ 25 ] and their cultivation requires additional cell culture media supplements [ 30 ]. In contrast, methods based on antibiotic resistance markers can be used to transform wild-type strains, but they require the addition of antibiotics to the growth media.…”