Sedimentation properties of chitosomal chitin synthetase from the wild-type strain and the 'slime' variant of Neurospora crassa.
Sedimentation properties of chitosomal chitin synthetase from the wild-type strain and the 'slime' variant of Neurospora crassa.
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来自粗糙脉孢菌野生型菌株和“粘液”变体的壳体几丁质合成酶的沉降特性。
DOI：
10.1016/s0304-4165(89)80010-8
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Bartnicki-García,S
中科院分区：
文献类型：
--
作者：
Martínez,JP;Giménez,G;Bracker,CE;Bartnicki-García,S
等密度离心后，观察到的细胞结构的沉降模式的显着差异的粗无细胞制剂从theNurospora crassawall-less '粘液'的变体和菌丝体野生型菌株。颗粒沉降的动力学研究表明，各种类型的亚细胞组分，所揭示的浊度，紫外吸收，多肽模式，和几丁质合成酶活性测定，沉淀相互独立。一个重要的特征是发现来自“粘液”的几丁质合成酶在中值比重1.1201 ± 0.0036处达到峰值，而来自野生型菌株的几丁质合成酶在较高的浮力密度（比重1.1349 ± 0.0024）处沉降。不同的培养条件或细胞破碎程序（渗透裂解或弹道破坏）似乎没有影响这种沉降行为。电子显微镜显示存在的壳聚糖体（微泡含有几丁质合成酶）的几丁质合成酶活性峰后获得的等密度离心的无细胞提取物从“粘液”和野生型菌株。两种几丁质合成酶浮力密度的差异。crassastries可能指向壳聚糖体微泡的化学组成的固有差异。在任何情况下，较低的浮力密度的“粘液”壳聚糖似乎是几个主要的改变亚细胞结构的沉降行为之一。这些变化可能与“粘液”无法形成细胞壁有关。
Marked differences in the pattern of sedimentation of cellular structures were observed after isopycnic centrifugation of crude cell-free preparations from theNeurospora crassawall-less ‘slime’ variant and mycelial wild-type strain. Kinetic studies of particle sedimentation showed that the various types of subcellular components, as revealed by turbidity, UV absorption, polypeptide patterns, and chitin synthetase activity determinations, sediment independently of one another. An important feature was the finding that chitin synthetase from ‘slime’ peaked at a median specific gravity of 1.1201 ± 0.0036, whereas that from wild-type strain sedimented at a higher buoyant density (specific gravity 1.1349 ± 0.0024). Different cultivation conditions or cell breakage procedures (osmotic lysis or ballistic disruption) did not seem to affect this sedimentation behavior. Electron microscopy revealed the presence of chitosomes (microvesicles containing chitin synthetase) in the chitin synthetase activity peaks obtained after isopycnic centrifugation of cell-free extracts from 'slime' and wild-type strains. The discrepancy in buoyant density of chitin synthetases from bothN. crassastrains might point to inherent differences in chemical composition of the chitosomal microvesicles. In any case, the lower buoyant density of ‘slime’ chitosomes appears to be one of several major alterations in sedimentation behavior of subcellular structures. These alterations might be related to the inability of ‘slime’ to make a cell wall.