[Production of SAM by recombinant Pichia pastoris].
To utilize Pichia pastoris to produce S-adenosyl-L-methionine (SAM), an intracellular expression vector harboring S. cerevisiae SAM2 was transformed into GS115. A recombinant strain having 2 copies of expression cassette was obtained through G418 resistance screening. This strain had higher SAM synthetase activity and higher SAM production capacity than the original strain, when cultured in medium containing methanol and methionine. The carbon source and nitrogen source of medium was optimized. The results showed SAM production by this strain was closely related to carbon metabolism. With supplementation of 0.2% glycerol every day from the beginning of 3rd day, this strain produced 1.58 g/L SAM when cultured in a medium containing 0.75% L-methionine and optimized carbon and nitrogen source after 6 days.
Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
Dong-Yang
DY
Li
Jian
J
Yu
Lu
L
Tian
Xin-Song
XS
Ji
Zhong-Yi
ZY
Yuan
D008716:Methionine Adenosyltransferase / Q000235:genetics / Q000378:metabolism*; D010843:Pichia / Q000235:genetics*; D011994:Recombinant Proteins / Q000378:metabolism; D012436:S-Adenosylmethionine / Q000096:biosynthesis*
D011994:Recombinant Proteins; D012436:S-Adenosylmethionine; D008716:Methionine Adenosyltransferase