[(2S)-pyrrolidine-2-carbonyl]azanium

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: [(2S)-pyrrolidine-2-carbonyl]azanium
• 化学式: C5H11N2O+
• 分子量: 115.15
• InChiKey: VLJNHYLEOZPXFW-BYPYZUCNSA-O

计算性质

• 辛醇/水分配系数(LogP)：
  -0.9
• 重原子数：
  8
• 可旋转键数：
  1
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.8
• 拓扑面积：
  59.7
• 氢给体数：
  2
• 氢受体数：
  1

反应信息

• 作为反应物：
  描述：

  水 、 [(2S)-pyrrolidine-2-carbonyl]azanium 生成 L-脯氨酸 、 铵
  参考文献：
  名称：

  S -Stereoselective piperazine-2-tert-butylcarboxamide hydrolase from Pseudomonas azotoformans IAM 1603 is a novel l-amino acid amidase

  摘要：

  An amidase acting on (R,S)‐piperazine‐2‐tert‐butylcarboxamide was purified from Pseudomonas azotoformans IAM 1603 and characterized. The enzyme acted S‐stereoselectively on (R,S)‐piperazine‐2‐tert‐butylcarboxamide to yield (S)‐piperazine‐2‐carboxylic acid. N‐terminal and internal amino acid sequences of the enzyme were determined. The gene encoding the S‐stereoselective piperazine‐2‐tert‐butylcarboxamide amidase was cloned from the chromosomal DNA of the strain and sequenced. Analysis of 2.1 kb of genomic DNA revealed the presence of two ORFs, one of which (laaA) encodes the amidase. This enzyme, LaaA is composed of 310 amino acid residues (molecular mass 34 514 Da), and the deduced amino acid sequence exhibits significant similarity to hypothetical and functionally characterized proline iminopeptidases from several bacteria. The laaA gene modified in the nucleotide sequence upstream from its start codon was overexpressed in Escherichia coli. The activity of the recombinant LaaA enzyme in cell‐free extracts of E. coli was 13.1 units·mg−1 with l‐prolinamide as substrate. This enzyme was purified to electrophoretic homogeneity by ammonium sulfate fractionation and two column chromatography steps. On gel‐filtration chromatography, the enzyme appeared to be a monomer with a molecular mass of 32 kDa. It had maximal activity at 45 °C and pH 9.0, and was completely inactivated in the presence of phenylhydrazine, Zn2+, Ag+, Cd2+ or Hg2+. LaaA had hydrolyzing activity toward l‐amino acid amides such as l‐prolinamide, l‐proline‐p‐nitroanilide, l‐alaninamide and l‐methioninamide, but did not act on the peptide substrates for the proline iminopeptidases despite their sequence similarity to LaaA. The enzyme also acted S‐stereoselectively on (R,S)‐piperidine‐2‐carboxamide, (R,S)‐piperazine‐2‐carboxamide and (R,S)‐piperazine‐2‐tert‐butylcarboxamide. Based on its specificity towards l‐amino acid amides, the enzyme was named l‐amino acid amidase. E. coli transformants overexpressing the laaA gene could be used for the S‐stereoselective hydrolysis of (R,S)‐piperazine‐2‐tert‐butylcarboxamide.

  DOI：

  10.1111/j.1432-1033.2004.04056.x