Feucht A, Lucet I, Yudkin M D, Errington J
Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK.
Mol Microbiol. 2001 Apr;40(1):115-25. doi: 10.1046/j.1365-2958.2001.02356.x.
The actin-like protein FtsA is present in many eubacteria, and genetic experiments have shown that it plays an important, sometimes essential, role in cell division. Here, we show that Bacillus subtilis FtsA is targeted to division sites in both vegetative and sporulating cells. As in other organisms FtsA is probably recruited immediately after FtsZ. In sporulating cells of B. subtilis FtsZ is recruited to potential division sites at both poles of the cell, but asymmetric division occurs at only one pole. We have now found that FtsA is recruited to only one cell pole, suggesting that it may play an important role in the generation of asymmetry in this system. FtsA is present in much higher quantities in B. subtilis than in Escherichia coli, with approximately one molecule of FtsA for five of FtsZ. This means that there is sufficient FtsA to form a complete circumferential ring at the division site. Therefore, FtsA may have a direct structural role in cell division. We have purified FtsA and shown that it behaves as a dimer and that it has both ATP-binding and ATP-hydrolysis activities. This suggests that ATP hydrolysis by FtsA is required, together with GTP hydrolysis by FtsZ, for cell division in B. subtilis (and possibly in most eubacteria).
肌动蛋白样蛋白FtsA存在于许多真细菌中，遗传实验表明它在细胞分裂中发挥着重要作用，有时甚至是必不可少的作用。在此，我们表明枯草芽孢杆菌FtsA定位于营养细胞和芽孢形成细胞的分裂位点。与其他生物体一样，FtsA可能在FtsZ之后立即被招募。在枯草芽孢杆菌的芽孢形成细胞中，FtsZ被招募到细胞两极的潜在分裂位点，但不对称分裂仅发生在一个极。我们现在发现FtsA仅被招募到一个细胞极，这表明它可能在该系统中不对称性的产生中发挥重要作用。FtsA在枯草芽孢杆菌中的含量比在大肠杆菌中高得多，大约每五个FtsZ分子对应一个FtsA分子。这意味着有足够的FtsA在分裂位点形成完整的圆周环。因此，FtsA可能在细胞分裂中具有直接的结构作用。我们已经纯化了FtsA，并表明它表现为二聚体，并且具有ATP结合和ATP水解活性。这表明FtsA的ATP水解与FtsZ的GTP水解一起，是枯草芽孢杆菌（可能还有大多数真细菌）细胞分裂所必需的。
