Ashikhmin Aleksandr, Makhneva Zoya, Bolshakov Maksim, Moskalenko Andrey
Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia.
Institute of Basic Biological Problems, Russian Academy of Sciences, Pushchino 142290, Russia.
J Photochem Photobiol B. 2014 Dec;141:59-66. doi: 10.1016/j.jphotobiol.2014.08.023. Epub 2014 Sep 16.
The processes of recovering colored-carotenoid (Car) biosynthesis in Car-less cells of the purple sulfur bacterium Ectothiorhodospira haloalkaliphila grown with diphenylamine (DPA-cells) have been studied. It has been found that (1) the rate of recovering colored-Car biosynthesis in the lag-phase is far ahead of the growth rate of the cells themselves; (2) several Cars (ζ-carotene, neurosporene etc.) act as intermediates in Car biosynthesis; (3) because filling the "empty" Car pockets in the LH1-RC complexes is faster than in LH2, available spirilloxanthin is preferentially incorporated into the nascent LH1-RC core particles; (4) as a consequence of the resulting lack of spirilloxanthin availability, the biosynthetic intermediates (anhydrorhodovibrin, rhodopin and lycopene) fill the empty nascent LH2 Car pockets. In the present report, we further discuss the process of colored Car incorporation into LH complexes during the recovery of Car biosynthesis in the DPA-cells of Ect.haloalkaliphila.
对在以二苯胺培养的嗜盐碱外硫红螺菌（Ectothiorhodospira haloalkaliphila）无类胡萝卜素细胞（DPA细胞）中恢复类胡萝卜素（Car）生物合成的过程进行了研究。结果发现：（1）延迟期恢复有色类胡萝卜素生物合成的速率远远超过细胞自身的生长速率；（2）几种类胡萝卜素（ζ-胡萝卜素、神经孢菌红素等）在类胡萝卜素生物合成中充当中间体；（3）由于在LH1-RC复合物中填充“空的”类胡萝卜素口袋比在LH2中更快，可用的螺菌黄素优先掺入新生的LH1-RC核心颗粒中；（4）由于由此导致的螺菌黄素供应不足，生物合成中间体（脱水红菌红素、玫红菌素和番茄红素）填充空的新生LH2类胡萝卜素口袋。在本报告中，我们进一步讨论了嗜盐碱外硫红螺菌DPA细胞中类胡萝卜素生物合成恢复过程中有色类胡萝卜素掺入LH复合物的过程。
