Open AccessPoly(γ‐ l ‐diaminobutanoic acid), a novel poly(amino acid), coproduced with poly(ɛ‐ l ‐lysine) by two strains of Streptomyces celluloflavus
Author(s) -
Takehara Munenori,
Saimura Masayuki,
Inaba Haruka,
Hirohara Hideo
Publication year - 2008
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2008.01261.x
Subject(s) - lysine , amino acid , streptomyces , bacteria , fermentation , aeration , chemistry , biochemistry , stereochemistry , nuclear chemistry , biology , organic chemistry , genetics
Two poly(ɛ‐ l ‐lysine) (ɛ‐PL) producer strains of Streptomyces celluloflavus secreted a novel polymeric substance into their culture broths along with ɛ‐PL. Three types of HPLC analysis plus one‐ and two‐dimensional 1 H and 13 C nuclear magnetic resonance experiments revealed that the secreted substance was poly(γ‐ l ‐diaminobutanoic acid) (γ‐PAB), an l ‐α,γ‐diaminobutanoic acid ( l ‐DAB) homopolymer linking between γ‐amino and α‐carboxylic acid functional groups. The γ‐PABs from the two strains had an identical chemical structure, and the same number‐average molecular weight of 2100–2200. No copolymers composed of the two amino acids l ‐DAB and l‐ lysine were found in either of the broths from the producers. Both strains coproduced high levels of the two poly(amino acid)s in the presence of SO 4 2− at pH 4.0 and 4.5 L min −1 aeration in a 5‐L jar fermentor. γ‐PAB exhibited strong inhibitory activities against various yeasts and weaker actions against bacteria than ɛ‐PL. γ‐PAB may have various biological functions similar to ɛ‐PL, and the use of γ‐PAB along with ɛ‐PL would be advantageous for technical applications in various fields.