Reference

Amino acid analyzer studies of the products of peroxide oxidation of cystine, lanthionine, and homocystine

Amino acid analyzer studies of the products of peroxide oxidation of cystine, lanthionine, and homocystine. Lipton, Samuel H.; Bodwell, C. E.; Coleman, Albert H., Jr. (Nutr. Inst., ARS, Beltsville, Md., USA). J. Agric. Food Chem., 25(3), 624-8 (English) 1977. CODEN: JAFCAU. DOCUMENT TYPE: Journal CA Section: 17 (Foods) Section cross-reference(s): 34 Mixts. of several S-contg. amino acid oxidn. products were formed in the oxidn. of L-cystine [56-89-3], lanthionine [922-55-4], or L-homocystine [626-72-2] by H2O2 in the presence of HCl. After 10 min at 100.degree. in 6% H2O2 and 0.8N HCl, cysteic acid [498-40-8] was the main oxidn. product of cystine; lanthionine sulfoxide [4271-36-7], lanthionine sulfone [17688-93-6], and unidentified products were also formed. In a similar oxidn. of lanthionine, lanthionine sulfoxide was the most abundant product; cysteic acid, lanthionine sulfone, and unidentified products were also formed. An identical oxidn. of homocystine afforded homolanthionine sulfoxide [59824-36-1] as the main product; homolanthionine sulfone [59824-35-0], and homocysteic acid [14857-77-3] were also formed. When homocystine was oxidized at 50.degree., homolanthionine was the principal product. However, when the HCl concn. was increased to 4.8N, homocysteic acid and homolanthionine sulfone were the main products. Sulfoxide products were distinguished by redn. with Me2S in the presence of HCl. Thus, they were converted to their corresponding sulfides and shifted to new chromatog. locations. These desulfurizations by H2O in the presence of HCl are discussed in relation to known chem. changes of amino acids, including lanthionine formation, occurring in alkali-treated foods and to the use of peroxide in food technol.

DNA-based diagnosis of methylmalonic aciduria and homocystinuria, cblC type in a Chinese patient presenting with mild developmental delay

All Rights Reserved. DNA-based diagnosis of methylmalonic aciduria and homocystinuria, cblC type in a Chinese patient presenting with mild developmental delay. Yuen, Yuet-Ping; Lam, Ching-Wan; Chan, Kwok-Yin; Lai, Chi-Kong; Tong, Sui-Fan; Chan, Yan-Wo (Department of Pathology, Princess Margaret Hospital, Hong Kong, Peop. Rep. China). Clinica Chimica Acta, 375(1-2), 171-172 (English) 2007 Elsevier Ltd. CODEN: CCATAR. ISSN: 0009-8981. DOCUMENT TYPE: Journal CA Section: 14 (Mammalian Pathological Biochemistry) Section cross-reference(s): 3 The DNA-based diagnosis of cobalamin C (cblC) of a 4-yr-old Chinese boy patient with early-onset cblC is described. Mutation anal. of the gene responsible for cblC, named MMACHC gene, showed that the patient was compd. heterozygous for a novel disease-causing mutation c.536537insAT and a known mutation C.394C>T. Although the biochem. defect underlying cblC is still unclear, existing evidence suggests that the defects of cblC affect steps that occur after the cellular uptake of cobalamin, common to the synthesis of both adenosylcobalamin and methylcobalamin and prior to the binding of the coenzymes to the resp. apoproteins. 13408-78-1 and 626-72-2 are just another two chemicals used in this study. .