School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-5000, USA.
School of Marine and Atmospheric Sciences, Stony Brook University, Stony Brook, NY 11794-5000, USA.
Protist. 2021 Feb;172(1):125793. doi: 10.1016/j.protis.2021.125793. Epub 2021 Jan 29.
Quahog Parasite Unknown (QPX) is a facultative parasite of the hard clam, Mercenaria mercenaria. Although it has been observed in clams since the 1960's and cultivated since the 1990's, conflicting reports on important aspects of its biology have prevented its formal description. 18S rRNA gene sequences identify QPX as a thraustochytrid, but its production of copious mucus is atypical for this group. There are also conflicting reports about whether QPX shares common features of thraustochytrids, such as the production of an ectoplasmic net and biflagellate zoospores. This study reaffirms the previous descriptions of zoospore production by QPX in culture, in multiple strains from several geographic locations, and provides detail on how to maintain QPX cultures under conditions that promote the production of zoospores. Furthermore, we describe new aspects of the life cycle not previously observed. Finally, we erect Mucochytrium quahogii gen. nov., sp. nov. to accommodate this unusual thraustochytrid.
夸霍格寄生虫未知种（QPX）是硬壳蛤，即 Mercenaria mercenaria 的兼性寄生虫。尽管自 20 世纪 60 年代以来就在蛤中观察到它，并自 20 世纪 90 年代以来进行了培养，但关于其生物学重要方面的相互矛盾的报告妨碍了其正式描述。18S rRNA 基因序列将 QPX 鉴定为厚壳蛤科的一员，但它大量产生粘液的特征与该组不同。关于 QPX 是否具有厚壳蛤科的共同特征，例如是否产生胞外网和双鞭毛游动孢子，也存在相互矛盾的报告。本研究再次证实了 QPX 在培养物中产生游动孢子的先前描述，涉及来自多个地理位置的多个菌株，并详细介绍了如何在促进游动孢子产生的条件下维持 QPX 培养物。此外，我们描述了以前未观察到的生命周期的新方面。最后，我们建立了 Mucochytrium quahogii 属。新种，以容纳这种不寻常的厚壳蛤科。
