Impairment of Respiratory Chain Function and Involvement of Alternative Respiratory Pathway in Mitochondria of Potato Tubers Infected by subsp. .

The significance of alternative respiratory pathway (AOXs) during the interaction between soft rot bacteria ( subsp. , (.)) and potato tubers is well-defined. However, the role of the AOXs in impaired mitochondrial respiratory chain function during the infection is yet to be studied. In this study, the results show that with the aggravation of infection of , the capacity for alternative respiration in mitochondria of potato tubers increased gradually. The mitochondrial membrane potential increased more significantly after infection with when the AOXs in potato tubers was partially blocked using salicylhydroxamic acid (SHAM) beforehand. In addition, the activity of complex III decreased more drastically while the activity of complex IV increased more significantly in the partial absence of the AOXs in the mitochondria. Furthermore, the mitochondrial endogenous respiration, mitochondrial respiratory state 3 and respiratory control rate (RCR) decreased more significantly and the value of RCR reached around 1.0 with the aggravation of infection of in the partially absence of AOXs in the mitochondria.