title: L-Norvaline and L-homoisoleucine formation by Serratia marcescens,.
abstract: Two unnatural amino acids were found as by-products in isoleucine fermentation from threonine by Serratia marcescens. These amino acids were identified as L-norvaline (2-aminopentanoic acid) and L-homoisoleucine (2-amino-4-methylhexanoic acid). Formation of L-norvaline and L-homoisoleucine was not observed when L-leucine was added to the medium. The leucine auxotroph derived from the isoleucine accumlator did not produce L-norvaline or L-homoisoleucine even during the accumulation of large amounts of isoleucine. It is suggested that L-norvaline and L-homoisoleucine formation is closely related to leucine biosynthesis.
mesh_terms: D007532:Isoleucine / Q000031:analogs & derivatives* / Q000096:biosynthesis; D009682:Magnetic Resonance Spectroscopy; D009154:Mutation; D012706:Serratia marcescens / Q000187:drug effects / Q000378:metabolism*; D013045:Species Specificity; D013055:Spectrophotometry, Infrared; D013912:Threonine / Q000494:pharmacology; D014633:Valine / Q000031:analogs & derivatives* / Q000096:biosynthesis
chemical_list: D007532:Isoleucine; D013912:Threonine; D014633:Valine