کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1942129 | 1052578 | 2015 | 12 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Time-resolved visible and infrared difference spectroscopy for the study of photosystem I with different quinones incorporated into the A1 binding site
دانلود مقاله + سفارش ترجمه
دانلود مقاله ISI انگلیسی
رایگان برای ایرانیان
کلمات کلیدی
PSIChl-ADDSPHQH bondelectron transfer - انتقال الکترونFourier transform infrared - تبدیل فوریه مادون قرمزRoom temperature - دمای اتاقFTIR - طیف سنج مادون قرمزphotosystem I - عکس سیستم منreaction center - مرکز واکنشmillisecond - میلی ثانیهNanosecond - نانوسکوردHydrogen bond - پیوند هیدروژنیCarbonyl - کربونیلChlorophyll-a - کلروفیل a
موضوعات مرتبط
علوم زیستی و بیوفناوری
علوم کشاورزی و بیولوژیک
دانش گیاه شناسی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Time-resolved visible and infrared difference spectroscopy for the study of photosystem I with different quinones incorporated into the A1 binding site Time-resolved visible and infrared difference spectroscopy for the study of photosystem I with different quinones incorporated into the A1 binding site](/preview/png/1942129.png)
چکیده انگلیسی
Room (298 K) and low (77 K) temperature time-resolved visible and infrared difference spectroscopy has been used to study photosystem I particles with phylloquinone (2-methyl-3-phytyl-1,4-naphthoquinone), menadione (2-methyl-1,4-naphthoquinone) and plastoquinone 9 (2,3-dimethyl-5-prenyl-l,4-benzoquinone), incorporated into the A1 binding site. Concentrated samples in short path-length (~ 5 μm) sample cells are typically used in FTIR experiments. Measurements were undertaken using standard “dilute” samples at 298 K, and concentrated (~ 5Ã) samples at both 298 and 77 K. No concentration induced alterations in the flash-induced absorption changes were observed. Concentrated samples in short path-length cells form a transparent film at 77 K, and could therefore be studied spectroscopically at 77 K without addition of a cryoprotectant. At 298 K, for photosystem I with plastoquinone 9/menadione/phylloquinone incorporated, P700+FA/Bâ radical pair recombination is characterized by a time constant of 3/14/80 ms, and forward electron transfer from A1Aâ to Fx by a time constant of 211/3.1/0.309 μs, respectively. At 77 K, for concentrated photosystem I with menadione/phylloquinone incorporated, P700+A1â radical pair recombination is characterized by a time constant of 240/340 μs, with this process occurring in 58/39% of the PSI particles, respectively. The origin of these differences is discussed. Marcus electron transfer theory in combination with kinetic modeling is used to simulate the observed electron transfer time constants at 298 K. This simulation allows an estimate of the redox potential for the different quinones in the A1 binding site.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Bioenergetics - Volume 1847, Issue 3, March 2015, Pages 343-354
Journal: Biochimica et Biophysica Acta (BBA) - Bioenergetics - Volume 1847, Issue 3, March 2015, Pages 343-354
نویسندگان
Hiroki Makita, Nan Zhao, Gary Hastings,