1. @entity8488 is oxidized to @entity37405 by an enzyme extracted from @entity1641 kidney, with sulphur or @entity41130 acting as a cofactor. It has been now found that, when the enzyme is omitted, sulphur and @entity41130 are able to catalyse the oxidation of @entity8488 to @entity16249 by molecular @entity26 . 2. @entity6693 may be used in catalytic amounts as a cofactor in the enzymic oxidation of @entity8488 to @entity37405 in the place of sulphur or @entity41130 . The effect of @entity6693 is not light-dependent and is not abolished by @entity39898 . Other redox dyes with E'(0) higher than that of @entity6693 are also used as cofactors. 3. A property common to all the cofactors is that they are necessary for the enzymic process in catalytic amounts, though they depress the final amount of @entity37405 produced when added over a critical concentration. All the cofactors share also the property of being catalysts for the non-enzymic oxidation of @entity8488 to @entity16249 . 4. @entity6693 is reduced by @entity8488 under anaerobic conditions, and is reoxidized in the presence of air. The rate of the reduction is not accelerated by the enzyme, indicating that the dye does not act in this reaction as a hydrogen carrier from the enzyme to @entity26 . The possible mechanism of action of @entity6693 and of the other cofactors is discussed.

The role of sulphur, @entity41130 and reducible dyes in the enzymic oxidation of XXXX to @entity37405 .

@entity1641 :: ('9796', 'Species') :: ['horse'] @entity26 :: ('MESH:D010100', 'Chemical') :: ['oxygen'] @entity8488 :: ('MESH:D003543', 'Chemical') :: ['cysteamine', 'Cysteamine'] @entity6693 :: ('MESH:D008751', 'Chemical') :: ['methylene blue', 'Methylene blue'] @entity41130 :: ('CHEBI:15138', 'Chemical') :: ['sulphide'] @entity39898 :: ('100060647(Tax:9796)', 'Gene') :: ['catalase'] @entity37405 :: ('MESH:C003949', 'Chemical') :: ['hypotaurine'] @entity16249 :: ('MESH:D003538', 'Chemical') :: ['cystamine']
@entity8488 :: (MESH:D003543,Chemical) :: ['cysteamine']
