Transport of nutrients by a thermophilic bacterium—reconstitution of vesicles from crystalline ATPase or solubilized alanine carrier

✍ Scribed by Yasuo Kagawa

• Publisher: John Wiley and Sons
• Year: 1976
• Tongue: English
• Weight: 406 KB
• Volume: 89
• Category: Article
• ISSN: 0021-9541
• DOI: 10.1002/jcp.1040890413

✦ Synopsis

A strain of aerobic thermophilic bacteria was selected in order to purify highly stable membrane proteins and to reconstitute proteoliposomes capable of transporting nutrients from them. These proteins responsible for the transport could be divided into (1) proteins which supply energy to the transporting system, and (2) specific nutrient carriers driven by the energy. The former included a stable ATPase (TF,) and a lipoprotein (TF,) which rendered TFI sensitive to energy transfer inhibitors. The complex of TF, and TF, could transport protons into reconstituted proteoliposomes upon hydrolysis of ATP. And one of the latter reported in this paper was alanine carrier protein which was driven by proton movement.

TFI was the first crystallized ATPase in biomembranes, and was reconstituted from its five different polypeptides, two of which were necessary for ATPase activity and four of which, for proton translocation. Purification of alanine carrier and reconstitution of proteoliposomes capable of alanine accumulation were also demonstrated.