Table 1.

Effects of various metabolites/inhibitors on [methyl-¹⁴C]SAM import by AaSAMT^a

Effector	SAM import (%)	SE (%)
None	100	±7
SAM	8	±2
SAH	6	±5
dc-SAH	34	±4
Sinefungin	69	±5
S-Adenosylcysteine	83	±3
ATP	97	±3
ADP	100	±5
AMP	102	±4
Methylthioadenosine	95	±3
Adenosine	130	±6
Adenine	95	±5
Cystathionine	101	±4
Methionine	98	±5
Homocysteine	99	±6
Cysteine	98	±4

^aUptake of [methyl-¹⁴C]SAM by recombinant AaSAMT was measured at a substrate concentration of 10 μM, and nonlabeled effectors were present in a 10-fold excess. Structures of the tested molecules are shown in Fig. S3 in the supplemental material. Import was stopped after 2 min. Rates of SAM uptake are net values (minus control, noninduced E. coli cells) given as percentage of nonaffected transport (set to 100%). Data are the means of data from four independent experiments. Standard errors are given.