Enhancement of ε-poly-L-lysine (ε-PL) production by a novel producer Bacillus cereus using metabolic precursors and glucose feeding.
Epsilon poly-L-lysine (ε-PL) is a homo-biopolymer with approximately 25-30 L-lysine residues. It is a promising natural biopolymer widely used in food and pharmaceutical industry. The present work reports enhanced production of ε-PL with a novel producer Bacillus cereus using amino acids and TCA cycle intermediates in the fermentation medium. Among the various amino acids and TCA cycle intermediates tested 2 mM L-aspartic acid and 5 mM citric acid gave ε-PL yield of 145.5 and 230 mg/L, respectively. A combination of citric acid after 24 h and L-aspartic acid after 36 h improved ε-PL yield from 85 mg/L (control) to 335 mg/L. Glucose feeding strategy along with metabolic precursors was employed which further enhanced ε-PL yield to 565 mg/L. Thus, more than sixfold increase in ε-PL yield was achieved suggesting the potential of Bacillus cereus as a novel ε-PL producer.
School of Biotechnology and Bioinformatics, D. Y. Patil University, C.B.D Belapur, Navi Mumbai, 400614, Maharashtra, India.
Anuj H
AH
Chheda
School of Biotechnology and Bioinformatics, D. Y. Patil University, C.B.D Belapur, Navi Mumbai, 400614, Maharashtra, India. madhavi.revankar@gmail.com.
Madhavi R
MR
Vernekar
Citric acid; Fermentation; L-Aspartic acid; Metabolic precursors; TCA cycle; ε-Poly-L-lysine