Moss Jessica A, Xiao Jie, Dungan Christopher F, Reece Kimberly S
The College of William and Mary, Virginia Institute of Marine Science, PO Box 1346, Gloucester Point, VA 23062, USA.
J Eukaryot Microbiol. 2008 Mar-Apr;55(2):117-30. doi: 10.1111/j.1550-7408.2008.00314.x.
Oysters were collected from coastal locations in China from 1999-2006 for parasite analyses by molecular, culture, and histological techniques. Polymerase chain reaction-based assays targeting the internal transcribed spacer (ITS) region of the ribosomal RNA gene complex were performed to detect the presence of Perkinsus species. Sequencing and phylogenetic analysis of amplified Perkinsus sp. DNAs indicated that a novel Perkinsus sp. infects Crassostrea hongkongensis, Crassostrea ariakensis, and other bivalve hosts from Fujian to Guangxi provinces in southern China. Prevalence of this Perkinsus sp. reaches as high as 60% in affected oyster populations. Analyses of nucleotide sequences of the rRNA ITS region and of large subunit rRNA and actin genes, consistently confirmed the genus affiliation of this Perkinsus sp., but distinguished it from currently accepted Perkinsus species. Parasite cell types, such as signet ring trophozoites of 2-8 microm diameter, were observed by histology, and application of both genus Perkinsus and Perkinsus species-specific in situ hybridization probes consistently labelled the same Perkinsus sp. cells in histological sections from infected oyster tissues. Combined phylogenetic and histological results support the identity of a new parasite species, Perkinsus beihaiensis n. sp.
1999年至2006年期间，从中国沿海地区采集牡蛎，采用分子、培养和组织学技术进行寄生虫分析。进行基于聚合酶链反应的检测，以核糖体RNA基因复合体的内部转录间隔区（ITS）为靶点，检测派琴虫属物种的存在。对扩增的派琴虫属DNA进行测序和系统发育分析表明，一种新型派琴虫感染香港巨牡蛎、近江牡蛎以及中国南方福建至广西等省份的其他双壳类宿主。在受影响的牡蛎种群中，这种派琴虫的感染率高达60%。对核糖体RNA ITS区域以及大亚基rRNA和肌动蛋白基因的核苷酸序列分析，一致确认了这种派琴虫的属归属，但将其与目前公认的派琴虫物种区分开来。通过组织学观察到寄生虫细胞类型，如直径为2-8微米的印戒滋养体，并且应用派琴虫属和派琴虫物种特异性原位杂交探针，在感染牡蛎组织的组织切片中一致标记相同的派琴虫属细胞。系统发育和组织学结果相结合，支持了一种新寄生虫物种——北海派琴虫（Perkinsus beihaiensis n. sp.）的鉴定。
