title: An HASApf-redoxin complex causing asymmetric catalytic oxidation via the regenerative formation of a reactive oxygen species.
abstract: A PP (pea)-HASApf-redoxin complex eluted from encapsulated PP gel with aeration displays asymmetric oxidation activity over 200 times greater than that of a similar protein expressed by E. coli cells. The intermediate spin, identified in the ESR spectrum, appears at g = 4.3 and g = 2.0, suggesting that an iron electron-transfer system for the asymmetric oxidation of secondary alcohols may be successfully created by the PP-HASApf-redoxin complex (39 kDa). FTIR experiments provided values νs(SO2) ≈ 950-1050 cm(-1) and νas(SO2) ≈ 1100-1200 cm(-1) for metal-bound sulfinate S-O and Fe-O vibrations. The sulfur and iron detected by physicochemical inspection (IC/ICP-AES) may facilitate the electron transport of a sulfate-iron complex (e.g., rubredoxin (6 kDa) or ferredoxin (9 kDa)) to the HASApf (21 kDa). The observations are consistently acceptable; i.e., the oxygen-driven PP-HASApf-redoxin complex functions regenerate via the successive asymmetric catalytic event - Fe(ii) + O2 → Fe(iii)-O-O(-) → Fe(iv) = O (oxidizing rac- or rac-) → Fe(ii) + H2O. Therefore, the use of a raw biomaterial as a PP-HASApf-redoxin complex-catalytic system for asymmetric oxidation is an important novelty, despite the apparent difficulties in working with pure dehydrogenase enzymatic/redox-cofactor systems for biotransformation.
authors.affiliation: Sanyo Shokuhin Co., Ltd R & D, 555-4 Asakura, Maebashi, Gunma 371-0811, Japan. hnagaoka@sanyofoods.co.jp.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Nagaoka
mesh_terms: D000464:Alginates / Q000737:chemistry; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D003545:Cysteine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism; D005782:Gels / Q000737:chemistry; D020723:Glucuronic Acid / Q000737:chemistry; D006418:Heme / Q000737:chemistry / Q000378:metabolism*; D006603:Hexuronic Acids / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D011551:Pseudomonas fluorescens / Q000737:chemistry / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*
chemical_list: D000464:Alginates; D001426:Bacterial Proteins; D005782:Gels; D006603:Hexuronic Acids; D017382:Reactive Oxygen Species; C545158:cysteine thiolate; D006418:Heme; D020723:Glucuronic Acid; D003545:Cysteine