Shewanella sp., the progenitors of bla_OXA‐48‐like genes are increasingly reported with the possession of different bla_OXA‐48‐like variants. This study aims to characterize bla_OXA‐731, a new variant of a bla_OXA‐48‐like gene identified in Shewanella sp. isolated from the aquatic environment in Myanmar. Phylogenetic analysis of the bla_OXA‐731 sequence with other bla_OXA‐48‐like variants showed that it has the highest nucleotide identity of 86.09% with bla_OXA‐48. However, the active site motifs in OXA‐731 were 100% identical to that in OXA‐48. Whole‐genome sequencing analysis showed that bla_OXA‐731 is not surrounded by any mobile genetic elements. The genetic context of bla_OXA‐731 was found as similar to other bla_OXA‐48‐like genes previously identified in Shewanella sp. S1 nuclease pulsed‐field gel electrophoresis followed by Southern blotting confirmed the location of bla_OXA‐731 in the chromosome of the Shewanella genome. Cloning and expression studies showed that OXA‐731 has β‐lactamase activity similar to OXA‐48 and OXA‐181, but it has no significant carbapenemase activity. Our results showed the significance of bla_OXA‐48‐like‐carrying Shewanella sp. in the spreading of bla_OXA‐48‐like genes in the community.

中文翻译：

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blaOXA -731，Shewanella sp。中一个新的染色体编码的blaOXA -48样变体。来自缅甸的水生环境。

越来越多地报道了bla _OXA-48样基因的祖先Shewanella sp。具有不同的bla _OXA-48样变体。这项研究旨在鉴定bla _OXA‐731，这是在Shewanella sp。中鉴定的bla _OXA‐48样基因的新变体。与缅甸的水生环境隔离。对bla _OXA‐731序列与其他bla _OXA‐48样变体的系统进化分析表明，它与bla _OXA‐48的核苷酸同一性最高，为86.09％。但是，OXA-731中的活性位点基序与OXA-48中的活性位点基序100％相同。全基因组测序分析表明，bla _OXA-731周围没有任何可移动的遗传元件。发现bla _OXA‐731的遗传背景与之前在Shewanella sp。中鉴定的其他bla _OXA‐48样基因相似。S1核酸酶脉冲场凝胶电泳，然后进行Southern印迹证实了bla _OXA-731在Shewanella染色体中的位置基因组。克隆和表达研究表明，OXA-731具有与OXA-48和OXA-181类似的β-内酰胺酶活性，但没有明显的碳青霉烯酶活性。我们的结果显示了携带bla _OXA-48样的希瓦氏菌的重要性。bla _OXA‐48样基因在社区中的传播。