title: Separation and Purification of ε-Poly-L-lysine with Its Colorimetric Determination Using Dipicrylamine.
abstract: A separation method for a biopolymer, ε-poly-L-lysine (εPL), with its colorimetric determination using a yellow anionic dye, dipicrylamine anion (DPA(-)), is presented. The εPL-producing culture broth was mixed with a NaDPA solution to precipitate the εPL in polycationic form with the DPA(-) anion. The precipitate was dissolved into acetonitrile (AN). The AN solution was yellowish, and gave an absorption maximum at around 420 nm. Thus, εPL in the culture broth can be assayed colorimetrically a with multiwell microtiter plate. By the addition of bis(triphenylphosphoranylidene)ammonium chloride, the polycationic εPL was precipitated from the AN solution as the hydrochloride salt. On the other hand, the DPA(-) anion remained in the AN solution as the quaternary ammonium salt. Thus, εPL larger than tetramer can be separated and purified after the high-throughput screening of the synthetic enzyme.
authors.affiliation: Department of Bioscience, Fukui Prefectural University.
authors.forename: Hajime
authors.initials: H
authors.lastname: Katano
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Kasahara
authors.forename: Kazunori
authors.initials: K
authors.lastname: Ushimaru
authors.forename: Chitose
authors.initials: C
authors.lastname: Maruyama
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Hamano
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D003124:Colorimetry / Q000379:methods*; D004396:Coloring Agents / Q000737:chemistry*; D015394:Molecular Structure; D010851:Picrates / Q000737:chemistry*; D011107:Polylysine / Q000096:biosynthesis / Q000302:isolation & purification*; D013302:Streptomyces / Q000378:metabolism*
chemical_list: D000097:Acetonitriles; D004396:Coloring Agents; D010851:Picrates; C011454:dipicrylamine; D011107:Polylysine; C032159:acetonitrile