کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5508360 | 1537687 | 2017 | 54 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Arachidonic acid is important for efficient use of light by the microalga Lobosphaera incisa under chilling stress
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کلمات کلیدی
EPANPQZEPDGLASQDGLC-PUFAChlVDEmonogalactosyldiacylglycerolMGDGdigalactosyldiacylglycerolDGDGDGTSViolaxanthin de-epoxidase - Violaxanthin de-epoksidaseChilling stress - استرس سردdihomo-γ-linolenic acid - اسید dihomo-γ-linolenicArachidonic acid - اسید آراشیدونیکEicosapentaenoic acid - اسید ایکوزاپنتانوئیکFatty acid desaturase - اسید لاکتیک اسیدlong-chain polyunsaturated fatty acid - اسید چرب اشباع نشده چای زنجیره ای طولانیzeaxanthin epoxidase - اکسیداز zeaxanthinFAD - بدtriacylglycerol - تری آسیل گلیسرول TAG یا triacylglycerols - تری گلیسرید یا تری آسیل گلیسرولNon-photochemical quenching - خنک سازی غیر فتوشیمیاییARA - در حال حاضرChlorophyll - سبزینه یا کلروفیلsulfoquinovosyldiacylglycerol - سولفوکینوواسیید دیسی سیل گلیسرئولMembrane fluidity - سیالیت غشاییPhotosystem - سیستم عکسCAR - ماشینwild type - نوع وحشیdry weight - وزن خشکCarotenoid - کاروتنوئیدglycerolipid - گلیسرولیپید
موضوعات مرتبط
علوم زیستی و بیوفناوری
بیوشیمی، ژنتیک و زیست شناسی مولکولی
زیست شیمی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
The oleaginous microalga Lobosphaera incisa (Trebouxiophyceae, Chlorophyta) contains arachidonic acid (ARA, 20:4 n â 6) in all membrane glycerolipids and in the storage lipid triacylglycerol. The optimal growth temperature of the wild-type (WT) strain is 25 °C; chilling temperatures (â¤Â 15 °C) slow its growth. This effect is more pronounced in the delta-5-desaturase ARA-deficient mutant P127, in which ARA is replaced with dihomo-γ-linolenic acid (DGLA, 20:3 n â 6). In nutrient-replete cells grown at 25 °C, the major chloroplast lipid monogalactosylglycerol (MGDG) was dominated by C18/C16 species in both strains. Yet ARA constituted over 10% of the total fatty acids in the WT MGDG as a component of C20/C18 and C20/C20 species, whereas DGLA was only a minor component of MGDG in P127. Both strains increased the percentage of 18:3 n â 3 in membrane lipids under chilling temperatures. The temperature downshift led to a dramatic increase in triacylglycerol at the expense of chloroplast lipids. WT and P127 showed a similarly high photochemical quantum yield of photosystem II, whereas non-photochemical quenching (NPQ) and violaxanthin de-epoxidation were drastically higher in P127, especially at 15 °C. Fluorescence anisotropy measurements indicated that ARA-containing MGDG might contribute to sustaining chloroplast membrane fluidity upon dropping to the chilling temperature. We hypothesize that conformational changes in chloroplast membranes and increased rigidity of the ARA-deficient MGDG of P127 at chilling temperatures are not compensated by trienoic fatty acids. This might 'lock' violaxanthin de-epoxidase in the activated state causing high constitutive NPQ and alleviate the risk of photodamage under chilling conditions in the mutant.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids - Volume 1862, Issue 9, September 2017, Pages 853-868
Journal: Biochimica et Biophysica Acta (BBA) - Molecular and Cell Biology of Lipids - Volume 1862, Issue 9, September 2017, Pages 853-868
نویسندگان
Boris Zorin, Dipasmita Pal-Nath, Alexandr Lukyanov, Sviatlana Smolskaya, Sofiya Kolusheva, Shoshana Didi-Cohen, Sammy Boussiba, Zvi Cohen, Inna Khozin-Goldberg, Alexei Solovchenko,