Electron microscopical structure analysis of yeast fatty-acid synthase at low resolution

• Published in: Biological chemistry Hoppe-Seyler Vol. 368; no. 1; pp. 19 - 36
• Main Authors: Hackenjos, W.A, Schramm, H.J
• Format: Journal Article
• Language: English
• Published: Germany 1987
• Subjects: electron microscopy; enzyme activity; Fatty Acid Synthases; fatty acids; Image Processing, Computer-Assisted; ligases; Microscopy, Electron; Protein Conformation; Saccharomyces cerevisiae - enzymology; yeasts
• ISSN: 0177-3593
• DOI: 10.1515/bchm3.1987.368.1.19

From an electron microscopical tilt series of the multi-enzyme complex yeast fatty-acid synthase eight three-dimensional molecular structures were obtained by three-dimensional reconstruction of single molecules. The structures confirm present concepts showing a well defined central wall and a sequential arrangement of protein domains in the form of "arches". Additional structural details as ring-shaped parts in the central walls are recognizable. Because of the flattening and the irregular structural deterioration of the single molecules three-dimensional averaging was only partially successful; however, a satisfactory average from five molecules could be obtained. Attempts to find the symmetry of the subunit arrangement by applying correlation methods and by establishing a novel type of correlation analysis ("correlation tables") did not yield a clear proof. However, several strong indications of D3 symmetry were found.