Stimulation of hydrogenation of linoleate in Treponema (Borrelia) sp, strain B2-5 by reduced methyl viologen and by reduced benzyl viologen.
نویسندگان
چکیده
A number of studies have been conducted to elucidate the properties and mechanism of the hydrogenation of Clg unsaturated fatty acids by rumen micro-organisms. Progress in this area has been reviewed by Dawson & Kemp (1970). During screening of a number of pure cultures of rumen bacteria, several species have been shown to hydrogenate linoleate to trans-octadecenoate (Polan, McNeill & Tove, 1964; Kemp & White, 1968; Sachan & Davis, 1969; Mills, Scott, Russell & Smith, 1970). A rumen bacillus has been reported to effect the complete hydrogenation of linoleate to stearate (White, Kemp & Dawson, 1970).
منابع مشابه
Pyruvate oxidation by the Reiter strain of Treponema phagedenis.
Spectrophotometric assays of pyruvate oxidation catalyzed by extracts of the Reiter strain of Treponema phagedenis indicated that viologen dyes, flavin nucleotides, and a ferric iron chelate, but not pyridine nucleotides, were utilized as electron acceptors. Benzyl viologen-linked activity partially sedimented during ultracentrifugation and appeared similar to clostridial pyruvate:ferredoxin ox...
متن کاملKinetic studies of a soluble up complex of nitrate reductase A from Escherichia coli Use of various ap mutants with altered p subunits
A soluble up complex of nitrate reductase can be obtained from a strain of Escheri(:h:hia r:oli that lacks the narl gene and expresses only the n and p subunits. The subunit contains four Fe-S centres and the a subunit contains the molybdenum cofactor, which is the site at which nitrate is reduced. Dcspite the lack of the y subunit of the complete enzyme, this complex can still catalyse the red...
متن کاملFerredoxin-linked reduction of metronidazole in Clostridium pasteurianum.
Clostridium pasteurianum cell-free extracts enzymatically reduced metronidazole when coupled by hydrogenase via reduced ferredoxin. A 5 mM concentration of methyl viologen, flavin adenine dinucleotide, or flavin mononucleotide could completely replace ferredoxin (0.05 mM) in the in vitro reduction assay system, whereas 5 mM benzyl viologen was less effective. However, when these electron carrie...
متن کاملPurification and properties of a sulfite reductase from leaf tissue.
Sulfite reductase (EC 1.8.1.2) has been purified lQO-fold from spinach leaves. The enzyme catalyzes the reduction cf sulfite to sulfide, with the use of reduced methyl viologen. NADH and NADPH are not capable of replacing reduced methyl viologen. A stoichiometry of 6 molecules of reduced methyl viologen oxidized per molecule of sulfide formed has been found. The enzyme, following treatment with...
متن کاملThe Reduction of Nitrate, Nitrite and Hydroxylamine to Ammonia by Enzymes from Cucurbita Pepo L. in the Presence of Reduced Benzyl Viologen as Electron Donor.
1. Enzyme systems from Cucurbita pepo have been shown to catalyse the reduction of nitrite and hydroxylamine to ammonia in yields about 90-100%. 2. Reduced benzyl viologen serves as an efficient electron donor for both systems. Activity of the nitrite-reductase system is directly related to degree of dye reduction when expressed in terms of the function for oxidation-reduction potentials, but a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- The Biochemical journal
دوره 125 3 شماره
صفحات -
تاریخ انتشار 1971