EVIDENCE FOR LACK OF DNA PHOTOREACTIVATING ENZYME IN HUMANS

被引：90

作者：

LI, YF

KIM, ST

SANCAR, A

机构：

[1] Biochemistry/Biophysics Department, School of Medicine, University of North Carolina, Chapel Hill

来源：

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA | 1993年 / 90卷 / 10期

关键词：

THYMINE DIMER; SKIN CANCER; MAMMALS; REPTILES;

D O I：

10.1073/pnas.90.10.4389

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

Photoreactivating enzyme (DNA photolyase; deoxyribocyclobutadipyrimidine pyrimidine-lyase, EC 4.1.99.3) repairs UV damage to DNA by utilizing the energy of near-UV/visible light to split pyrimidine dimers into monomers. The enzyme is widespread in nature but is absent in certain species in a seemingly unpredictable manner. Its presence in humans has been a source of considerable controversy. To help resolve the issue we used a very specific and sensitive assay to compare photoreactivation activity in human, rattle-snake, yeast, and Escherichia coli cells. Photolyase was easily detectable in E. coli, yeast, and rattlesnake cell-free extracts but none was detected in cell-free extracts from HeLa cells or human white blood cells with an assay capable of detecting 10 molecules per cell. We conclude that humans most likely do not have DNA photolyase.

引用

页码：4389 / 4393

页数：5

共 45 条

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[2]

Cleaver J. E., 1989, METABOLIC BASIS INHE, V2, P2949

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