Department of Biotechnology, Kyoto Institute of Technology, Kyoto 606-8585, Japan.
J Agric Food Chem. 2011 Nov 23;59(22):12238-45. doi: 10.1021/jf203145p. Epub 2011 Nov 2.
Ferrochelatase (FECH), the enzyme at the last step of the heme-biosynthetic pathway, is involved in the formation of Zn-protoporphyrin via an iron-removal reaction of heme. To improve the efficacy of the formation of Zn-protoporphyrin from heme, the use of recombinant FECHs from porcine, yeast, and bacteria was examined. Incubation of FECH with myoglobin in the presence of ascorbic acid and cysteine resulted in the efficient conversion of myoglobin-heme to Zn-protoporphyrin. Exogenously added recombinant yeast FECH facilitates the production of Zn-protoporphyrin from myoglobin-heme and heme in meat, via the replacement of iron in the protoporphyrin ring by zinc ions. A large amount of Zn-protoporphyrin was also generated by the catalysis of FECH using an intact piece of meat as a substrate. These findings can open up possible approaches for the generation of a nontoxic bright pigment, Zn-protoporphyrin, to shorten the incubation time required to produce dry-cured ham.
亚铁螯合酶(FECH)是血红素生物合成途径的最后一步酶,通过血红素的铁去除反应参与锌原卟啉的形成。为了提高血红素形成锌原卟啉的功效,研究了来自猪、酵母和细菌的重组 FECH 的用途。在抗坏血酸和半胱氨酸存在下,FECH 与肌红蛋白孵育导致肌红蛋白-血红素有效地转化为锌原卟啉。外源添加的重组酵母 FECH 通过锌离子取代原卟啉环中的铁,促进肉中肌红蛋白-血红素和血红素产生锌原卟啉。使用完整的肉块作为底物,FECH 的催化作用也产生了大量的锌原卟啉。这些发现为生成无毒的亮色素锌原卟啉开辟了可能的途径,以缩短生产干腌火腿所需的孵育时间。