AUTHOR=Ergin Çağri , Şengül Mustafa , Aksoy Levent , Döğen Aylin , Sun Sheng , Averette Anna F. , Cuomo Christina A. , Seyedmousavi Seyedmojtaba , Heitman Joseph , Ilkit Macit 

TITLE=Cryptococcus neoformans Recovered From Olive Trees (Olea europaea) in Turkey Reveal Allopatry With African and South American Lineages

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=9

YEAR=2019

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2019.00384

DOI=10.3389/fcimb.2019.00384

ISSN=2235-2988

ABSTRACT=<p><italic>Cryptococcus</italic> species are life-threatening human fungal pathogens that cause cryptococcal meningoencephalitis in both immunocompromised and healthy hosts. The natural environmental niches of <italic>Cryptococcus</italic> include pigeon (<italic>Columba livia</italic>) guano, soil, and a variety of tree species such as <italic>Eucalyptus camaldulensis, Ceratonia siliqua, Platanus orientalis</italic>, and <italic>Pinus</italic> spp. Genetic and genomic studies of extensive sample collections have provided insights into the population distribution and composition of different <italic>Cryptococcus</italic> species in geographic regions around the world. However, few such studies examined <italic>Cryptococcus</italic> in Turkey. We sampled 388 <italic>Olea europaea</italic> (olive) and 132 <italic>E</italic>. <italic>camaldulensis</italic> trees from seven locations in coastal and inland areas of the Aegean region of Anatolian Turkey in September 2016 to investigate the distribution and genetic diversity present in the natural <italic>Cryptococcus</italic> population. We isolated 84 <italic>Cryptococcus neoformans</italic> strains (83 <italic>MAT</italic>α and 1 <italic>MAT</italic><bold>a</bold>) and 3 <italic>Cryptococcus deneoformans</italic> strains (all <italic>MAT</italic>α) from 87 (22.4% of surveyed) <italic>O</italic>. <italic>europaea</italic> trees; a total of 32 <italic>C</italic>. <italic>neoformans</italic> strains were isolated from 32 (24.2%) of the <italic>E</italic>. <italic>camaldulensis</italic> trees, all of which were <italic>MAT</italic>α. A statistically significant difference was observed in the frequency of <italic>C</italic>. <italic>neoformans</italic> isolation between coastal and inland areas (<italic>P</italic> &lt; 0.05). Interestingly, the <italic>MAT</italic><bold>a</bold><italic>C</italic>. <italic>neoformans</italic> isolate was fertile in laboratory crosses with VNI and VNB <italic>MAT</italic>α tester strains and produced robust hyphae, basidia, and basidiospores, thus suggesting potential sexual reproduction in the natural population. Sequencing analyses of the <italic>URA5</italic> gene identified at least five different genotypes among the isolates. Population genetics and genomic analyses revealed that most of the isolates in Turkey belong to the VNBII lineage of <italic>C</italic>. <italic>neoformans</italic>, which is predominantly found in southern Africa; these isolates are part of a distinct minor clade within VNBII that includes several isolates from Zambia and Brazil. Our study provides insights into the geographic distribution of different <italic>C</italic>. <italic>neoformans</italic> lineages in the Mediterranean region and highlights the need for wider geographic sampling to gain a better understanding of the natural habitats, migration, epidemiology, and evolution of this important human fungal pathogen.</p>