STM2360 is a gene located in a small operon of undetermined function in Salmonella enterica serovar Typhimurium LT2. The amino acid sequence of STM2360 shows significant similarity (∼30% identity) to diaminopimelate decarboxylase (DapDC), a Fold III pyridoxal-5′-phosphate (PLP) dependent enzyme involved in l-lysine biosynthesis. We have found that the protein coded by STM2360 has a previously undocumented catalytic activity, d-ornithine/d-lysine decarboxylase (DOKDC). The reaction products, cadaverine and putrescine, respectively, were identified by NMR and mass spectrometry. The substrate specificity of DOKDC is d-Lysine > d-Ornithine. This is the first pyridoxal-5′-phosphate dependent decarboxylase identified to act on d-amino acids. STM2358, located in the same operon, has ornithine racemase activity. This suggests that the physiological substrate of the decarboxylase and the operon is ornithine. Homologs of STM2360 with high sequence identity (>80%) are found in other common enterobacteria, including species of Klebsiella, Citrobacter, Vibrio and Hafnia, as well as Clostridium in the Firmicutes, and Pseudomonas.

STM2360是位于肠炎沙门氏菌血清鼠伤寒沙门氏菌LT2中一个功能不确定的小操纵子中的基因。所述的STM2360节目显著相似性（约30％同一性），以二氨基庚二酸脱羧酶（DapDC），参与一个折III的吡哆醛-5'-磷酸（PLP）依赖性酶的氨基酸序列升赖氨酸的生物合成。我们已经发现，由STM2360编码的蛋白质具有以前未记录的催化活性，即d-鸟氨酸/ d-赖氨酸脱羧酶（DOKDC）。通过NMR和质谱分别鉴定了反应产物尸胺和腐胺。DOKDC的底物特异性为d-赖氨酸>  d-鸟氨酸。这是第一个被鉴定为对d-氨基酸起作用的依赖吡ido醛5'-磷酸的脱羧酶。位于同一操纵子中的STM2358具有鸟氨酸消旋酶活性。这表明脱羧酶和操纵子的生理底物是鸟氨酸。具有高序列同一性的STM2360同源物（> 80％）在其他常见肠细菌中发现，包括物种克雷伯氏菌，柠檬酸杆菌属，弧菌属和哈夫尼菌属，以及梭菌在厚壁菌门，和假单胞菌属。