| Title | Cloning of the Gene for Na+/Serine-Threonine Symporter (sstT) from Haemophilus influenzae Rd and Characteristics of the Transporter |
|---|---|
| Author | Young-Mog Kim * |
| Address | Institute of Agricultural Science & Technology, Kyungpook National University, Daegu 702-701, Korea (Received April 18, 2003 / Accepted May 28, 2003) |
| Bibliography | Journal of Microbiology, 41(3),202-206, 2003, |
| DOI | |
| Key Words | Haemophilus influenzae Rd, Na^+/serine-threonine symporter |
| Abstract | A protein, exhibiting a high similarity to the major serine transporter of Escherichia coli, SstT, was found in Haemophilus influenzae Rd. A Na+-stimulated serine transport activity was also detected in the cells. The gene (sstT) for the Na^+/serine symporter from the chromosome of H. influenzae was cloned, and the properties of the transporter investigated. The serine transport activity was stimulated by Na^+. The uptake of Na^+ was elicited by the addition of serine or threonine into the cells, supporting the idea that these amino acids are transported by a mechanism of Na^+/substrate symport. No uptake of H^+ was elicited by the influx of serine. The serine transport via the SstT of H. influenzae was inhibited by excess threonine, which was used as another substrate. The K_m and the V_max values for the serine transport were 2.5 mM and 14 nmol/min/mg protein, respectively. |
| Download PDF | 413-120.pdf |