Watt Steven Alexander, Wilke Andreas, Patschkowski Thomas, Niehaus Karsten
Department of Genetics, Faculty of Biology, University of Bielefeld, D-33501 Bielefeld, Germany.
Proteomics. 2005 Jan;5(1):153-67. doi: 10.1002/pmic.200400905.
The extracellular proteome of Xanthomonas campestris pv. campestris (Xcc) cultivated in minimal medium was isolated from the cell-free culture supernatant and separated by two-dimensional gel electrophoresis. This technique resolved 97 clearly visible protein spots, which were excised, digested with trypsin and identified on the basis of their peptide mass fingerprints generated by matrix assisted laser desorption/ionisation-time of flight-mass spectrometry. Using this approach 87 different proteins could be distinguished. The Signal P software predicted putative signal peptides for 53% of the extracellular proteins. These proteins are probably transported over the inner membrane and are localized in the periplasm, the outer membrane or secreted into the extracellular space. Among the secreted proteins are 11 degradative enzymes, which are involved in pathogenesis of Xcc. The proteins without obvious secretion signals are known to serve functions in the cytosol. How the cytosolic proteins are delivered to the extracellular space remains unclear.
在基本培养基中培养的野油菜黄单胞菌野油菜致病变种（Xcc）的细胞外蛋白质组，是从无细胞培养上清液中分离出来的，并通过二维凝胶电泳进行分离。这项技术分离出了97个清晰可见的蛋白点，将这些蛋白点切下，用胰蛋白酶消化，并根据基质辅助激光解吸/电离飞行时间质谱产生的肽质量指纹图谱进行鉴定。采用这种方法可以区分出87种不同的蛋白质。信号肽预测软件预测出53%的细胞外蛋白质含有假定的信号肽。这些蛋白质可能通过内膜转运，定位于周质、外膜或分泌到细胞外空间。分泌蛋白中有11种降解酶，它们参与Xcc的致病过程。已知没有明显分泌信号的蛋白质在细胞质中发挥作用。目前尚不清楚细胞质蛋白是如何被递送到细胞外空间的。
