TIME-RESOLVED ABSORPTION STUDIES OF NATIVE ETIOLATED OAT PHYTOCHROME

被引:66
作者
ZHANG, CF
FARRENS, DL
BJORLING, SC
SONG, PS
KLIGER, DS
机构
[1] UNIV CALIF SANTA CRUZ,DEPT CHEM & BIOCHEM,SANTA CRUZ,CA 95064
[2] UNIV NEBRASKA,DEPT CHEM,LINCOLN,NE 68588
关键词
D O I
10.1021/ja00038a019
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The phototransformation kinetics of native oat phytochrome from etiolated seedling shoots of Avena sativa was investigated by laser photolysis experiments at 10-degrees-C. The phototransformation from the red-absorbing form (Pr) to the far-red-absorbing form (Pfr) was initiated by 7-ns (fwhm) laser pulses at 638 nm. The transient absorption difference spectra in the UV and visible regions were recorded from 100 ns to 800 ms after photolysis by a gated optical multichannel analyzer system. A global fitting procedure employing a singular value decomposition method was used to simultaneously analyze the difference spectra at various times after photolysis. The global analysis of the laser photolysis data shows that the phototransformation from Pr to Pfr involves five kinetic intermediates. At 10-degrees-C the apparent lifetimes associated with these intermediates are 7.4-mu-s, 89.5-mu-s, 7.6 ms, 42.4 ms, and at least 266 ms. It is possible to fit the transient absorption data with kinetic models involving two parallel pathways or sequential pathways with equilibria at certain stages of the phototransformation. The formation of Pfr involves an unbranched reaction. Discussions of the possible kinetic mechanisms of the phototransformation and the absorption spectra of the intermediates derived from these models are presented.
引用
收藏
页码:4569 / 4580
页数:12
相关论文
共 57 条
[1]  
BAMFORD CH, 1969, CHEM KINETICS MODERN, V24
[2]   TIME-RESOLVED CIRCULAR-DICHROISM OF NATIVE OAT PHYTOCHROME PHOTOINTERMEDIATES [J].
BJORLING, SC ;
ZHANG, CF ;
FARRENS, DL ;
SONG, PS ;
KLIGER, DS .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 1992, 114 (12) :4581-4588
[3]  
BJORLING SC, 1991, THESIS U CALIFORNIA
[4]   THE PHOTOPHYSICS AND PHOTOCHEMISTRY OF THE PLANT PHOTOSENSOR PIGMENT PHYTOCHROME [J].
BRASLAVSKY, SE .
PURE AND APPLIED CHEMISTRY, 1984, 56 (09) :1153-1165
[5]   FLUORESCENCE LIFETIMES AND RELATIVE QUANTUM YIELDS OF 124-KILODALTON OAT PHYTOCHROME IN H2O AND D2O SOLUTIONS [J].
BROCK, H ;
RUZSICSKA, BP ;
ARAI, T ;
SCHLAMANN, W ;
HOLZWARTH, AR ;
BRASLAVSKY, SE ;
SCHAFFNER, K .
BIOCHEMISTRY, 1987, 26 (05) :1412-1417
[6]   PURIFICATION AND SPECTROSCOPIC PROPERTIES OF 124-KDA OAT PHYTOCHROME [J].
CHAI, YG ;
SINGH, BR ;
SONG, PS ;
LEE, J ;
ROBINSON, GW .
ANALYTICAL BIOCHEMISTRY, 1987, 163 (02) :322-330
[7]   PHOTOTRANSFORMATION KINETICS OF UNDEGRADED OAT AND PEA PHYTOCHROME INITIATED BY LASER FLASH EXCITATION OF THE RED-ABSORBING FORM [J].
CORDONNIER, MM ;
MATHIS, P ;
PRATT, LH .
PHOTOCHEMISTRY AND PHOTOBIOLOGY, 1981, 34 (06) :733-740
[8]   EVIDENCE FOR A SEQUENTIAL PATHWAY FROM PR TO PFR OF THE PHOTOTRANSFORMATION OF 124-KDA OAT PHYTOCHROME [J].
EILFELD, P ;
EILFELD, P ;
VOGEL, J ;
MAURER, R .
PHOTOCHEMISTRY AND PHOTOBIOLOGY, 1987, 45 (06) :825-830
[9]  
EILFELD P, 1985, Z NATURFORSCH C, V40, P109
[10]   ON THE PRIMARY PHOTOPROCESS OF 124-KILODALTON PHYTOCHROME [J].
EILFELD, P ;
EILFELD, P ;
RUDIGER, W .
PHOTOCHEMISTRY AND PHOTOBIOLOGY, 1986, 44 (06) :761-769