Sobukawa Hideto, Ibaraki Masato, Kano Rui, Ito Takaaki, Suzuki Kazuyuki, Kamata Hiroshi, Hasegawa Atsuhiko
Department of Pathobiology, Nihon University School of Veterinary Medicine.
Med Mycol J. 2013;54(4):341-4. doi: 10.3314/mmj.54.341.
Prototheca zopfii is an achlorophyllic alga that is ubiquitous around cow sheds. The alga is associated with bovine mastitis, which causes a reduction in milk production and secretion of thin watery milk containing white flakes. Isolates of P. zopfii from bovine mastitis were almost all identified as P. zopfii genotype 2, suggesting that it is the main causative agent of bovine protothecal mastitis. The ability to differentiate between genotype 1 and genotype 2 is therefore very important for preventing bovine mastitis. In this study, high resolution melting real-time PCR (PCR-HRM) analysis of the protothecal 18S rDNA domain successfully differentiated between genotypes of P. zopfii in less than 3 hours, while conventional sequence analysis requires more than 48 hours to differentiate between genotypes. PCR-HRM analysis clustered P. zopfii genotype 1 isolates separately from P. zopfii genotype 2 isolates, indicating that this molecular typing method is an effective tool for rapidly diagnosing bovine protothecal mastitis.
威克海姆原藻是一种无叶绿素的藻类，在牛舍周围普遍存在。这种藻类与牛乳腺炎有关，牛乳腺炎会导致产奶量下降，并分泌出含有白色薄片的稀薄水样牛奶。从牛乳腺炎中分离出的威克海姆原藻几乎都被鉴定为威克海姆原藻基因型2，这表明它是牛原藻性乳腺炎的主要病原体。因此，区分基因型1和基因型2的能力对于预防牛乳腺炎非常重要。在本研究中，对原藻18S rDNA区域进行的高分辨率熔解实时PCR（PCR-HRM）分析在不到3小时内成功区分了威克海姆原藻的基因型，而传统序列分析则需要超过48小时才能区分基因型。PCR-HRM分析将威克海姆原藻基因型1分离株与威克海姆原藻基因型2分离株分开聚类，表明这种分子分型方法是快速诊断牛原藻性乳腺炎的有效工具。
