FIG 4.

(A) Relative expression of “Ca. Liberibacter asiaticus” ATP/ADP translocase (nttA [CLIBASIA_RS01005]) in both its citrus and psyllid hosts. Transcript abundances of nttA and prfA were normalized against expression levels of chromosomal reference gene gyrB within each host. Bars represent averages ± the standard errors of the means (n = 3). Asterisks represent significant differences (P < 0.05) in the transcript abundance with respect to prfA within each host. (B) Time- and dose-dependent [α-³²P]ATP uptake into L. crescens cells expressing “Ca. Liberibacter asiaticus” nttA. Five-day-old wild-type BT-1 cells and transformed BT-1/pMJ056 cells expressing nttA were incubated in the presence of [α-³²P]ATP at room temperature. At the indicated time points, 500-μl culture aliquots were withdrawn and washed twice to remove external [α-³²P]ATP. The cells were resuspended in PBS and scintillation fluid. The amount of radioactive ATP taken up by the cells was expressed as counts per minute (cpm). Bars represent average data ± the standard errors of at least three independent experiments.