Details

Autor(en) / Beteiligte

• Amzel, L M
• McKinney, M
• Narayanan, P
• Pedersen, P L

Titel

Structure of the mitochondrial F1 ATPase at 9-A resolution

Ist Teil von

• Proceedings of the National Academy of Sciences - PNAS, 1982-10, Vol.79 (19), p.5852-5856

Ort / Verlag

United States: National Acad Sciences

Erscheinungsjahr

1982

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• The soluble portion (F1 ATPase) of the mitochondrial ATP-synthesizing system is a multisubunit enzyme of molecular weight 380,000. It is composed of five different subunits, alpha, beta, gamma, and epsilon. The subunit stoichiometry is not known but there are strong suggestions that it is alpha 3 beta 3 gamma delta epsilon. We have determined the three-dimensional structure of the F1 ATPase of rat liver mitochondria to 9-A resolution by using x-ray diffraction techniques. The molecule appears to be formed by two equivalent halves, each formed by three regions of approximately equal size. These regions form a distorted hexagonal or octahedral arrangement. None of the regions form closed symmetrical trimers in the complex. It is proposed that, if the subunit stoichiometry is alpha 3 beta 3 gamma delta epsilon, the major subunits exist in at least two different environments in the complex. In this arrangement, the different copies of the major subunits are functionally not equivalent. This observation appears to offer a natural explanation of the complicated binding and labeling data of F1 ATPases.