S-Ribosylhomocysteinase（LuxS） is the key enzyme in the synthetic pathway of a quorum sensing autoinducer AI-2. LuxS from a 2,3-butanediol produced strain Klebisella pneumoniae CICC 10011 was cloned and characterized...S-Ribosylhomocysteinase（LuxS） is the key enzyme in the synthetic pathway of a quorum sensing autoinducer AI-2. LuxS from a 2,3-butanediol produced strain Klebisella pneumoniae CICC 10011 was cloned and characterized. The luxS gene is composed of 540 bp with 172 amino acids encoded. The Km value for S-ribosylhomo- cysteine（SRH） was （27±1） umol/L, kcat was （0.112±0.004） s-1 and kcat/Km was 4.4×103 L umol-1·s-1 at 25 ℃. LuxS was activated by divalent metal ions, the highest activity was detected with Co2＋ form, followed by Mg2＋, Ba2＋, Mn2＋, Fe2＋ and Ca2＋, and activation constant for Co2＋ is （16±2） umol/L.展开更多
基金Supported by the National High-Tech Research and Development Program of China(No.2009AA05Z443)
文摘S-Ribosylhomocysteinase（LuxS） is the key enzyme in the synthetic pathway of a quorum sensing autoinducer AI-2. LuxS from a 2,3-butanediol produced strain Klebisella pneumoniae CICC 10011 was cloned and characterized. The luxS gene is composed of 540 bp with 172 amino acids encoded. The Km value for S-ribosylhomo- cysteine（SRH） was （27±1） umol/L, kcat was （0.112±0.004） s-1 and kcat/Km was 4.4×103 L umol-1·s-1 at 25 ℃. LuxS was activated by divalent metal ions, the highest activity was detected with Co2＋ form, followed by Mg2＋, Ba2＋, Mn2＋, Fe2＋ and Ca2＋, and activation constant for Co2＋ is （16±2） umol/L.
