Cooper C R, Haycocks N G
WHO Collaborating Center for Tropical Diseases, Department of Pathology, University of Texas Medical Branch, Galveston 77555-0609, USA.
J Eukaryot Microbiol. 2000 Jan-Feb;47(1):24-8. doi: 10.1111/j.1550-7408.2000.tb00006.x.
Most species of Penicillium are considered relatively benign with respect to causing human disease. However, one species, P. marneffei, has emerged as a significant pathogen particularly among individuals who live in Southeast Asia and are concurrently infected with the human immunodeficiency virus. While environmental and epidemiological studies have yet to resolve the reason for the heightened virulence of P. marneffi, one characteristic does distinguish this fungus from other Penicillium species. Whereas the latter grow as monomorphic moulds bearing typical asexual propagules (conidia), P. marneffei is thermally dimorphic. At room temperature, P. marneffei exhibits the morphology characteristic of the genus. In contrast to other Penicillia, though, P. marneffei grows as a yeast-like entity (arthroconidium) when found in diseased tissue or cultivated at 37 degrees C. Studies in our laboratory have focused on the differential gene expression between the mould and arthroconidial phases. Many of the genes whose expression differs during mould-to-arthrocondium transition are related to energy metabolism. A better understanding of gene expression during morphogenesis in P. marneffei may help detect unique target sites or cellular processes that can be exploited in the development of antifungal agents or immunomodulation therapies.
就引发人类疾病而言，多数青霉菌物种被认为相对无害。然而，其中一种马尔尼菲青霉菌已成为一种重要的病原体，尤其在生活于东南亚且同时感染人类免疫缺陷病毒的个体中。虽然环境和流行病学研究尚未确定马尔尼菲青霉菌毒力增强的原因，但有一个特征确实将这种真菌与其他青霉菌物种区分开来。后者以带有典型无性繁殖体（分生孢子）的单态霉菌形式生长，而马尔尼菲青霉菌是温度双态性的。在室温下，马尔尼菲青霉菌呈现出该属的形态特征。不过，与其他青霉菌不同的是，当在患病组织中发现或在37摄氏度下培养时，马尔尼菲青霉菌以酵母样实体（关节孢子）的形式生长。我们实验室的研究集中在霉菌期和关节孢子期之间的差异基因表达上。在从霉菌向关节孢子转变过程中表达不同的许多基因都与能量代谢有关。更好地了解马尔尼菲青霉菌形态发生过程中的基因表达，可能有助于发现可在抗真菌药物开发或免疫调节治疗中加以利用的独特靶点或细胞过程。
