Isolation of mitochondria from Saccharomyces cerevisiae using magnetic bead affinity purification

• Published in: PloS one 2018-04, Vol.13 (4), p.e0196632-e0196632
• Main Authors: Liao, Pin-Chao, Boldogh, Istvan R, Siegmund, Stephanie E, Freyberg, Zachary, Pon, Liza A
• Format: Article
• Language: English
• Subjects: Affinity chromatography; Antifungal agents; Baking yeast; Beads; Biology and Life Sciences; Centrifugation; Chromatography, Affinity - methods; Coating effects; Contaminants; CRISPR; Cryoelectron Microscopy; Cytochrome; Cytochrome-c oxidase; Density; Density gradients; Electron Transport Complex IV - metabolism; Genetic modification; Histidine - genetics; Histidine - metabolism; Imidazole; Insertion; Magnetics; Mitochondria; Mitochondria - metabolism; Mitochondria - ultrastructure; Mitochondrial Membrane Transport Proteins - genetics; Mitochondrial Membrane Transport Proteins - metabolism; Mitochondrial Proteins - metabolism; Nickel; Nitrilotriacetic acid; Physical Sciences; Protein transport; Purification; Recombinant Proteins - chemistry; Recombinant Proteins - genetics; Recombinant Proteins - metabolism; Research and Analysis Methods; Saccharomyces cerevisiae; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae Proteins - genetics; Saccharomyces cerevisiae Proteins - metabolism; Translocase; Ultracentrifugation; Ultrastructure
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0196632

Isolated mitochondria are widely used to study the function of the organelle. Typically, mitochondria are prepared using differential centrifugation alone or in conjunction with density gradient ultracentrifugation. However, mitochondria isolated using differential centrifugation contain membrane or organelle contaminants, and further purification of crude mitochondria by density gradient ultracentrifugation requires large amounts of starting material, and is time-consuming. Mitochondria have also been isolated by irreversible binding to antibody-coated magnetic beads. We developed a method to prepare mitochondria from budding yeast that overcomes many of the limitations of other methods. Mitochondria are tagged by insertion of 6 histidines (6xHis) into the TOM70 (Translocase of outer membrane 70) gene at its chromosomal locus, isolated using Ni-NTA (nickel (II) nitrilotriacetic acid) paramagnetic beads and released from the magnetic beads by washing with imidazole. Mitochondria prepared using this method contain fewer contaminants, and are similar in ultrastructure as well as protein import and cytochrome c oxidase complex activity compared to mitochondria isolated by differential centrifugation. Moreover, this isolation method is amenable to small samples, faster than purification by differential and density gradient centrifugation, and more cost-effective than purification using antibody-coated magnetic beads. Importantly, this method can be applied to any cell type where the genetic modification can be introduced by CRISPR or other methods.