Glucose transport in the extremely thermoacidophilic Sulfolobus solfataricus involves a high-affinity membrane-integrated binding protein
Glucose transport in the extremely thermoacidophilic Sulfolobus solfataricus involves a high-affinity membrane-integrated binding protein
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DOI：
10.1128/jb.181.14.4285-4291.1999
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发表时间：
1999-07-01
影响因子：
3.2
通讯作者：
Konings, WN
中科院分区：
文献类型：
--
作者：
Albers, SV;Elferink, MGL;Konings, WN
古菌Sulfolobus solfataricus在80 ℃和pH 2.5至3.5的碳源如酵母提取物、胰蛋白胨和各种糖上生长最佳。细胞迅速积累葡萄糖。这种转运活性涉及膜结合的葡萄糖结合蛋白，其以非常高的亲和力（Kd为0.43 μ M）与其底物相互作用，并在非常低的pH值（低至pH 0.6）下保持高的葡萄糖亲和力。用去污剂提取结合蛋白，并纯化至均一为65-kDa糖蛋白。在S. solfataricus P2基因组的氨基酸序列。序列分析表明，该蛋白通过氨基末端跨膜段锚定到膜上。相邻的基因编码两个膜蛋白和一个ATP结合亚基，在相反的方向转录，而同源基因簇Pyrococcus horikoshii OT 3中被发现被组织在一个操纵子。这些数据表明S. solfataricus利用结合蛋白依赖性ATP结合盒转运蛋白摄取葡萄糖。
The archaeon Sulfolobus solfataricus grows optimally at 80 degrees C and pH 2.5 to 3.5 on carbon sources such as yeast extracts, tryptone, and various sugars. Cells rapidly accumulate glucose. This transport activity involves a membrane-bound glucose-binding protein that interacts with its substrate with very high affinity (K-d of 0.43 mu M) and retains high glucose affinity at very low pH values (as low as pH 0.6). The binding protein was extracted with detergent and purified to homogeneity as a 65-kDa glycoprotein. The gene coding for the binding protein was identified in the S. solfataricus P2 genome by means of the amino-terminal amino acid sequence of the purified protein. Sequence analysis suggests that the protein is anchored to the membrane via an amino-terminal transmembrane segment. Neighboring genes encode two membrane proteins and an ATP-binding subunit that are transcribed in the reverse direction, whereas a homologous gene cluster in Pyrococcus horikoshii OT3 was found to be organized in an operon. These data indicate that S. solfataricus utilizes a binding-protein-dependent ATP-binding cassette transporter for the uptake of glucose.