Carbamylation of Human Lens γ-crystaUins:Relevance to Cataract Formation  

作　　者：Xuyang Liu Shaozhen Li 

机构地区：[1]Zhongshan Ophthalmic Center,Sun Yat-Sen University of Medical Sciences Guangzhou 510060,China

出　　处：《眼科学报》1993年第3期136-142,157,共8页Eye Science

基　　金：This work was supported by Chinese Medicine Foundation

摘　　要：Cigarette smoking is a main source of cyanide in human body,which can be taken as a risk factor of cataract formation.In this study,combined gas chromatography and mass spectrum(GC/MS)was used todetermine the amino acid hydantoin after the incubation of soluble humanlensγ-crystallins with cyanate.The carbamylated amino acids obtained bythis procedure are alanine and hlycine,which are N-terminal amino acids ofγ-crystallin,and leucine.The aggregate,which can be observed incarbamylatedγ_1-crystallin on SDS-PAGE,may be related to the formation of disulfide and non-disulfide covalent bonds,and it seems that Y₂and Yy-crystallins can not be aggregated to any great extend.The results in this study indicate that the GC/MS is an effective method for analyzing the carbamylation of lens proteins;y-crystallin may play a very important role in the formation of cataract associated with accumulation of cyanate in human body,such as heavy smoking.Cigarette smoking is a main source of cyanide in human body,which can be taken as a risk factor of cataract formation.In this study,combined gas chromatography and mass spectrum(GC/MS)was used todetermine the amino acid hydantoin after the incubation of soluble humanlensγ-crystallins with cyanate.The carbamylated amino acids obtained bythis procedure are alanine and hlycine,which are N-terminal amino acids ofγ-crystallin,and leucine.The aggregate,which can be observed incarbamylatedγ_1-crystallin on SDS-PAGE,may be related to the formation of disulfide and non-disulfide covalent bonds,and it seems that Y₂and Yy-crystallins can not be aggregated to any great extend.The results in this study indicate that the GC/MS is an effective method for analyzing the carbamylation of lens proteins;y-crystallin may play a very important role in the formation of cataract associated with accumulation of cyanate in human body,such as heavy smoking.

关 键 词：CARBAMYLATION HYDANTOIN GC/MS Iens crystallin smokjng CATARACT 

分 类 号：R77[医药卫生—眼科]