Microstructure of poly(gamma-glutamic acid) produced by Bacillus subtilis consisting of clusters of D- and L-glutamic acid repeating units.
Poly(gamma-glutamic acid) (PGA) produced by a strain of Bacillus subtilis was partially hydrolyzed into various oligopeptides so that the dipeptide fraction was isolated by the preparative thin-layer chromatography. HPLC analysis was applied to the detection of each of the four stereoisomers in this fraction using chemically synthesized authentic samples. The fraction consisted of N-gamma- d-glutamyl- d-glutamic acid, N-gamma- l-glutamyl- l-glutamic acid, N-gamma- d-glutamyl- l-glutamic acid, and N-gamma- l-glutamyl- d-glutamic acid at a ratio of 5.9:6.0:1.0:1.0. On the basis of this result, a model was proposed for the microstructure of the bacterial PGA, in which d- and l-glutamic acid repeating units are alternately linked in a single chain of the molecule.
Wang
Fei
F
Suntory Institute for Bioorganic Research, Osaka, Japan.
Ishiguro
Masaji
M
Mutsukado
Mai
M
Fujita
Ken-Ichi
K
Tanaka
Toshio
T
D001412:Bacillus subtilis / Q000378:metabolism*; D018698:Glutamic Acid / Q000032:analysis*; D006868:Hydrolysis; D011099:Polyglutamic Acid / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000737:chemistry; D013237:Stereoisomerism
C511775:poly(gamma-glutamic acid); D011099:Polyglutamic Acid; D018698:Glutamic Acid