Morphogenesis and developmental interactions in myxobacteria.
Morphogenesis and developmental interactions in myxobacteria.
复制标题
粘细菌的形态发生和发育相互作用。
DOI：
10.1126/science.806967
复制
发表时间：
1975
期刊：
影响因子：
56.9
通讯作者：
M. Dworkin
中科院分区：
文献类型：
--
作者：
J. Wireman;M. Dworkin
试图确定粘孢子发育的生化相关M。xanthus的发现有助于缩短粘孢子的正常发育形成，并直接在液体培养中诱导它们的形成。这是通过添加几种可能的诱导剂之一来实现的（23）。在这些条件下，营养细胞转化为粘孢子迅速，定量，和相对同步。具有这种效果的化合物是那些具有伯醇或仲醇基团的化合物（如甘油，乙二醇，丁醇和苯乙醇）（23）以及二甲基亚砜（24）。营养细胞逐渐变短并变圆，直到约100至120分钟时，完整的营养细胞转化为圆形的、光学无触觉的、抗性的休眠细胞，类似于子实体中形成的细胞。然而，生化变化至少持续了另外6小时。大分子变化。在粘孢子的诱导过程中。在大分子合成中有实质性的变化。这些变化是针对：（i）细胞的结构转换，（ii）将其转换为代谢静止状态，以及（iii）为随后的萌发做好准备。在粘孢子形成过程中，DNA合成持续进行，直到Rosenberg等人提出，完成现有的几轮复制;不启动新的几轮复制（25）。净RNA合成立即停止，尽管发生了增加的周转（24）。Okano等人的数据表明，在粘孢子形成过程中合成的一小部分RNA是粘孢子所特有的（26）。此外，Foster和教区（27）发现粘孢子核糖体30 S亚基的物理性质和蛋白质亚基组成存在差异。在形态转化期间，净蛋白质合成继续进行; 2小时后，净蛋白质合成停止，但蛋白质周转率仍很高（28）。
Attempts to determine the biochemical correlates of myxospore development in M. xanthus were aided by the discovery that it is possible to short-circuit the nor-mal developmental formation of myxospores and induce their formation directly in liquid culture. This was done by the ad-dition of one of several possible inducers (23). Under these conditions, vegetative cells were converted to myxospores rapidly, quantitatively, and relatively synchronously. The compounds that had this effect were those with primary or secondary alcohol groups (such as glycerol, ethylene glycol, butanol, and phenethyl alcohol)(23) as well as dimethyl sulfoxide (24). The vegetative cells progressively shortened and rounded up until, at about 100 to 120 minutes, the complete vegetative cells were converted to round, optically refractile, re-sistant resting cells similar to those formed in fruiting bodies. Biochemical changes however, continued to take place for an additional 6 hours at least. Macromolecular changes. During myxospore induction in M. xanthus there are substantial changes in macromolecular synthesis. These changes are directed toward:(i) the structural conversion of the cell,(ii) converting it to a state of metabolic quiescence, and (iii) preparing it for subsequent germination. During myxospore formation DNA synthesis continues until, as has been suggested by Rosenberg et al., existing rounds of replication are completed; no new rounds are initiated (25). Net RNA synthesis ceases immediately, although increased turnover takes place (24). The data of Okano et al. indicate that a smallfraction of RNA synthesized during myxospore formation is unique to the myxospore (26). In addition, Foster and Parish (27) have found differences in the physical properties and in the protein subunit composition of the 30S subunit of the myxospore ribosome. Net protein synthesis continues during the morphological conversion; after 2 hours, net protein synthesis ceases but a high rate of protein turnover continues (28).