The reducing activity of S-aminoethylcysteine ketimine and similar sulfur-containing ketimines.
S-aminoethylcysteine ketimine and other sulfur-containing similar ketimines reduce molecular oxygen and phospho-18-tungstate (Folin Marenzi reagent), although the sulfur atom is formally present in the non reducing thioether form. We have now found that 2,6-diclorophenolindophenol, some ferrihemoproteins and other reagents are also reduced by this group of ketimines. Ferricytochrome c is reduced faster than methemoglobin, metmyoglobin and free hematin, whereas horse radish peroxidase compound I is reduced at once. These results indicate a wider reducing activity of this type of ketimine. The oxidation of ketimines by ferric cytochrome c appears a relevant finding pointing to a new possible way of enzymatic modification of sulfur-ketimines in tissues.
Solinas
S P
SP
Dipartimento di Scienze Biochimiche, A. Rossi Fanelli, Università di Roma La Sapienza, Italy.
Pecci
L
L
Montefoschi
G
G
Cavallini
D
D
D015086:2,6-Dichloroindophenol / Q000737:chemistry*; D000603:Amino Acids, Sulfur / Q000737:chemistry*; D003545:Cysteine / Q000031:analogs & derivatives* / Q000737:chemistry; D003574:Cytochrome c Group / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry*; D006420:Hemeproteins / Q000737:chemistry*; D006427:Hemin / Q000737:chemistry; D006735:Horseradish Peroxidase / Q000737:chemistry; D007097:Imines; D008786:Metmyoglobin / Q000737:chemistry; D010084:Oxidation-Reduction; D010772:Phosphotungstic Acid / Q000737:chemistry
D000603:Amino Acids, Sulfur; D003574:Cytochrome c Group; D005290:Ferric Compounds; D006420:Hemeproteins; D007097:Imines; D010772:Phosphotungstic Acid; D008786:Metmyoglobin; C000204:S-2-aminoethyl cysteine; C035497:thialysine ketimine; D006427:Hemin; D015086:2,6-Dichloroindophenol; D006735:Horseradish Peroxidase; D003545:Cysteine