Distribution of the mevalonate and glyceraldehyde phosphate/pyruvate pathways for isoprenoid biosynthesis in unicellular algae and the cyanobacterium Synechocystis PCC 6714
Distribution of the mevalonate and glyceraldehyde phosphate/pyruvate pathways for isoprenoid biosynthesis in unicellular algae and the cyanobacterium Synechocystis PCC 6714
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DOI：
10.1042/bj3330381
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发表时间：
1998-07-15
影响因子：
4.1
通讯作者：
Rohmer, M
中科院分区：
文献类型：
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作者：
Disch, A;Schwender, J;Rohmer, M
异戊烯基二磷酸，通用类异戊二烯前体，可以通过两种不同的生物合成途径产生：通过乙酸/甲羟戊酸（MVA）途径，或通过最近确定的MVA-独立的甘油醛磷酸/丙酮酸途径。通过掺入[1-C-13]葡萄糖并分析在类异戊二烯中发现的所得标记模式，这两种途径很容易区分。这种方法被成功地应用于几个单细胞藻类提出的异养生长条件下，并允许识别的途径，利用类异戊二烯生物合成。所有类异戊二烯检查（甾醇，植醇，类胡萝卜素）的绿色藻类小球藻fusca和莱茵衣藻合成通过差距/丙酮酸途径，在另一个以前研究的绿色藻类，栅藻，这也表明在这项研究中，以合成泛醌由相同的MVA-独立的路线。在红色的Cyanidium caldarium和植物中的Ochromonas danica观察到一个明确的二分法：在高等植物中，甾醇是通过MVA途径形成的，而叶绿体类异戊二烯（植物醇在Cy。caldarium和O. danica和O. danica）通过差距/丙酮酸途径合成。与此相反，裸藻Euglena gracilis合成麦角甾醇，以及植醇，通过乙酸/MVA路线。使用[1-C-13]-和[6-C-13]-葡萄糖，用蓝细菌集胞藻PCC 6714进行类似的饲喂实验。两个类异戊二烯检查，植醇和β-胡萝卜素，被证明具有来自差距/丙酮酸途径的典型标记模式。
Isopentenyl diphosphate, the universal isoprenoid precursor, can be produced by two different biosynthetic routes: either via the acetate/mevalonate (MVA) pathway, or via the more recently identified MVA-independent glyceraldehyde phosphate/ pyruvate pathway. These two pathways are easily differentiated by incorporation of [l-C-13]glucose and analysis of the resulting labelling patterns found in the isoprenoids. This method was successfully applied to several unicellular algae raised under heterotrophic growth conditions and allowed for the identification of the pathways that were utilized for isoprenoid biosynthesis. All isoprenoids examined (sterols, phytol, carotenoids) of the green algae Chlorella fusca and Chlamydomonas reinhardtii were synthesized via the GAP/pyruvate pathway, as in another previously investigated green alga, Scenedesmus obliquus, which was also shown in this study to synthesize ubiquinone by the same MVA-independent route. In the red alga Cyanidium caldarium and in the Chrysophyte Ochromonas danica a clear dichotomy was observed: as in higher plants, sterols were formed via the MVA route, whereas chloroplast isoprenoids (phytol in Cy. caldarium and O. danica and beta-carotene in O. danica) were synthesized via the GAP/pyruvate route. In contrast, the Euglenophyte Euglena gracilis synthesized ergosterol, as well as phytol, via the acetate/MVA route. Similar feeding experiments were performed with the cyanobacterium Synechocystis PCC 6714 using [1-C-13]- and [6-C-13]-glucose. The two isoprenoids examined, phytol and beta-carotene, were shown to have the typical labelling pattern derived from the GAP/pyruvate route.