Properties of Mitochondria Prepared by Two Different Isolation Procedures From the Cotyledons of Germinating Bean Seedlings

Mitochondria from 1-day-old bean cotyledons were isolated bya ‘slow’ isolation procedure involving a wash andby a ‘rapid’ procedure. The mitochondria isolatedby the ‘rapid’ procedure were more tightly coupledthan those isolated by the ‘slow’ procedure. Anexogenous supply of cytochrome c or NAD was shown to improvethe activity of mitochondria isolated by the ‘slow’procedure, but not those isolated by the ‘rapid’procedure. The phosphorylative abilities of the latter weremuch greater than the former and were retained for longer periods.It was found that there was a leakage of NAD out of the mitochondria.