Transports pyruvate with a high affinity and specificity. The process is driven by the proton motive force (PubMed:29061664). Under nutrient limiting conditions, mediates the uptake of pyruvate, thus enabling it to be used as a carbon source for the growth and survival (PubMed:29061664). Part of a nutrient-sensing regulatory network composed of the two-component regulatory systems BtsS/BtsR and YpdA/YpdB, and their respective target proteins, BtsT and YhjX (PubMed:24659770). H(+)(out) + pyruvate(out) = H(+)(in) + pyruvate(in) Transport is inhibited by the protonophores 2,4-dinitrophenol (DNP) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP), but not by ionophores such as valinomycin, nonactin and nigericin. Optimum pH is 7.5. Interacts with BtsS and YpdA. Strongly induced at the onset of the stationary-growth phase. Expression is dependent on the BtsS/BtsR two-component regulatory system, and on cAMP and the cAMP receptor protein (CRP). Repressed by LeuO. Monocistronic operon. Regulated at post-transcriptional level by CsrA (PubMed:24659770). Belongs to the peptide transporter carbon starvation (CstA) (TC 2.A.114) family.