Penicillium marneffeiInfection and Recent Advances in the Epidemiology and Molecular Biology Aspects

Abstract

SUMMARY Penicillium marneffei infection is an important emerging public health problem, especially among patients infected with human immunodeficiency virus in the areas of endemicity in southeast Asia, India, and China. Within these regions, P. marneffei infection is regarded as an AIDS-defining illness, and the severity of the disease depends on the immunological status of the infected individual. Early diagnosis by serologic and molecular assay-based methods have been developed and are proving to be important in diagnosing infection. The occurrence of natural reservoirs and the molecular epidemiology of P. marneffei have been studied; however, the natural history and mode of transmission of the organism remain unclear. Soil exposure, especially during the rainy season, has been suggested to be a critical risk factor. Using a highly discriminatory molecular technique, multilocus microsatellite typing, to characterize this fungus, several isolates from bamboo rats and humans were shown to share identical multilocus genotypes. These data suggest either that transmission of P. marneffei may occur from rodents to humans or that rodents and humans are coinfected from common environmental sources. These putative natural cycles of P. marneffei infection need further investigation. Studies on the fungal genetics of P. marneffei have been focused on the characterization of genetic determinants that may play important roles in asexual development, mycelial-to-yeast phase transition, and the expression of antigenic determinants. Molecular studies have identified several genes involved in germination, hyphal development, conidiogenesis, and yeast cell polarity. A number of functionally important genes, such as the malate synthase- and catalase-peroxidase protein-encoding genes, have been identified as being upregulated in the yeast phase. Future investigations pertaining to the roles of these genes in host-fungus interactions may provide the key knowledge to understanding the pathogenicity of P. marneffei.

Eukaryotic microbes, species recognition and the geographic limits of species: examples from the kingdom Fungi

“…To make determinations of reproductive mode even more difficult, often fungi that never have been observed to undergo sexual reproduction nevertheless have populations consistent with recombination (Taylor et al 1999). In fact, only one fungus that lacks the morphology of sexual reproduction has been shown to be exclusively asexual and clonal by population genetic criteria, Penicillium marneffei (Fisher et al 2005;Vanittanakom et al 2006). Many fungi that generally self-fertilize (i.e.…”

Role of the yakA gene in morphogenesis and stress response in Penicillium marneffei

“…It is one of the common opportunistic infections in patients with AIDS, especially in south-east Asia (Boyce & Andrianopoulos, 2013;Vanittanakom et al, 2006). Penicilliosis due to P. marneffei is fatal if untreated.…”

“…Penicilliosis due to P. marneffei is fatal if untreated. The growth of P. marneffei can be divided into two phases based on natural growth and during infection (Andrianopoulos, 2002;Cooper & Vanittanakom, 2008;Vanittanakom et al, 2006). At 25 u C, P. marneffei grows as a filamentous (mould) form and displays a yellowish green powdery to velvety colony with red pigment diffused into the medium.…”

Ocular Penicillium Infection Presenting as Combined Rhegmatogenous and Serous Retinal Detachment in an Immunocompetent Patient

“…Penicillium marneffei was first described in 1959 after isolation from a bamboo rat [2]. It is now endemic in tropical Asia (following the HIV pandemic in Asia) [1,[3][4][5].…”

“…Penicillium marneffei is an emerging cause of fatal systemic mycosis in patients infected with the human immunodeficiency virus (HIV) [1][2][3][4]. Although both immunocompetent and immunocompromised individuals can become infected, it is extremely rare to diagnose systemic P. marneffei infections in patients negative for the human immunodeficiency virus (HIV).…”