Early mortality syndrome (EMS) in cultivated shrimp is of complex aetiology. One of the causes is acute hepatopancreatic necrosis disease (AHPND) caused by unique Vibrio isolates that carry two Pir^vp toxin genes, but other causes of EMS remain mostly unexplained. Here, we describe the discovery of a Shewanella isolate TH2012^T from an EMS/AHPND outbreak pond and demonstrate its virulence for shrimp (the mean lethal concentration of 10⁵ colony‐forming units per millilitre by immersion challenge) accompanied by distinctive histopathology, particularly of the ventral nerve cord and lymphoid organ but also including the digestive tract. On the basis of its complete genome sequence, multilocus phylogenetic trees, digital DNA–DNA hybridization analysis and differential phenotypic characteristics, we propose that Shewanella isolate TH2012^T represents a novel species, separated sufficiently from the type strains S. litorisediminis and S. amazonensis to justify naming it Shewanella khirikhana sp. nov. Analysis of the TH2012^T genome revealed no homologues of the Pir^vp toxin genes but revealed a number of other potential virulence factors. It constitutes the first Shewanella isolate reported to be pathogenic to shrimp.

中文翻译：

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希瓦内拉（Shewanella khirikhana）十一月 -从养殖池塘分离出的虾病原体，表现出早期死亡综合症。

养殖虾的早期死亡综合症（EMS）具有复杂的病因。原因之一是由携带两个Pir ^vp毒素基因的独特弧菌分离株引起的急性肝胰腺坏死病（AHPND），但其他原因引起的EMS仍无法解释。在这里，我们描述了从EMS / AHPND爆发池塘中发现的Shewanella分离物TH2012 ^T的发现，并证明了其对虾的毒性（平均致死浓度为10 ⁵浸没攻击后每毫升的菌落形成单位），并伴有独特的组织病理学特征，尤其是腹侧神经索和淋巴器官，还包括消化道。它的完整基因组序列，多位系统发生树，数字DNA-DNA杂交分析和差的表型特征的基础上，我们建议，希瓦氏菌分离物TH2012 ^Ť表示一个新种，从型菌株充分分离S. litorisediminis和S.亚马孙到将其命名为Shewanella khirikhana sp。十一月 TH2012 ^T基因组的分析表明没有Pir ^vp的同源物毒素基因，但揭示了许多其他潜在的毒力因子。它构成了首个对虾具有致病性的希瓦氏菌分离株。