Biosynthesis of lysine in Rhodotorula glutinis: role of pipecolic acid.
Glutamate-alpha-ketoadipate transaminase, saccharopine reductase, and saccharopine dehydrogenase activities were demonstrated in extracts of Rhodotorula glutinis but alpha-aminoadipate reductase activity could not be measured in whole cells or in extracts. Lysine auxotroph lys1 grew in the presence of L-lysine or DL-alpha-aminoadipate and incorporated radioactivity from DL-alpha-amino-[I-14C]adipate into lysine during growth. Growing wild-type cells converted L-[U-14C]lysine into alpha-amino-[14C]adipate, suggesting both biosynthetic and degradative roles for alpha-aminoadipate. Lysine auxotrophs lys1, lys2 and lys3 of R. glutinis, unlike lysine auxotrophs of Saccharomyces cerevisiae, satisfied their growth requirement with L-pipecolate. Moreover, extracts of wild-type R. glutinis catalysed the conversion of L-pipecolate to alpha-aminoadipate-delta semialdehyde. These results suggest a biosynthetic role for L-pipecolate in R. glutinis but not in S. cerevisiae.
D000272:Adipates / Q000378:metabolism; D000445:Aldehyde Oxidoreductases / Q000378:metabolism; D002250:Carbon Radioisotopes; D002474:Cell-Free System; D002855:Chromatography, Thin Layer; D005971:Glutamates; D008239:Lysine / Q000096:biosynthesis* / Q000378:metabolism; D003904:Mitosporic Fungi / Q000201:enzymology / Q000378:metabolism*; D009154:Mutation; D010088:Oxidoreductases / Q000378:metabolism; D010089:Oxidoreductases, N-Demethylating / Q000378:metabolism; D010875:Pipecolic Acids / Q000378:metabolism*; D000637:Transaminases / Q000378:metabolism
D000272:Adipates; D002250:Carbon Radioisotopes; D005971:Glutamates; D010875:Pipecolic Acids; D010088:Oxidoreductases; D000445:Aldehyde Oxidoreductases; D010089:Oxidoreductases, N-Demethylating; D000637:Transaminases; D008239:Lysine