The stability of isolated yeast mritochondria during refrigerated storage has been sttudied (9), but the comparable stability of m)iltochondria from a higher plant has not been reported. Preliminary experiments indicated that tom,a)to fruiit mitochondria were stable for at least 1 day after isolation anid showed a delayed response to the first addition of ADP whiile oxidizing succinate. Suich a dellayed responnse to the first addition of ADP with succinate as suibstratte h!as been reported for mitoch,ondria from seve,ral plant species and tissues (2, 6,9,13,14). Wiskich and Bonner (14) attributed this deliay to inihibitory amounts of oxa,loacetate, wrhile Verleur ( 13) attributed it to the quality of the mitochondria. In view of the conflicting interpretations of this delay, and th,e stability of tomato fru,iit mitocjhondria, a study of sucecinate oxidationi in these mitochondria was condtuted. This paper reporits effects dtue to storage and some of the factors controll1ing the delayed respon.se ito the first addition of ADP.
Materials and MethodsTomaito fruit (Lycopersi(cmn (sclienton7 AiMill.) were picked in the greenhouse or field the day of use. Mature green fruit were used except for table I which also includes data from tomato fruit vine-ripened in the greenhouse 5 d'ays past incipient coloring. The entire mitochonndrial isolation was done at 00 to 40. A sample of 62.5 g of outer perlicarp was rinised, chilled in crtushed ice, and then