The diversity of soil yeast in Cameroon and Saudi Arabia

Abstract

Yeasts are unicellular microorganisms that belong to the kingdom of fungi. Yeasts are found in a diverse range of habitats, including soil, sugar-rich surfaces on the fruit and flowers of plants, and on the surface of plants and animals. Yeast plays an important role in soil by participating in nutrient cycles and mineralization processes. In contrast to the various studies investigating soil yeasts in Western countries, there is a dearth of research investigating soil yeasts in Africa and the Middle East. In these projects, we collected 493 soil samples from nine different geographical locations in Cameroon, and 562 soil samples from six geographical locations in Saudi Arabia. I identified yeast isolates by using the culture-based method and the fungal barcode sequence at the ITS region. In addition, the yeast species were analyzed using PCR- fingerprinting to investigate the genetic variation among strains within the same species. In sum, we have isolated and identified a total of 110 yeast isolates from Cameroon as well as a total of 114 yeast isolates from Saudi Arabia. Our results showed that soil samples from different regions in Cameroon had different yeast colonization (0%-56%), with the highest found in northwest Cameroon. The Saudi Arabian yeast isolation was different from those in Cameroon, with less diversity; the isolation rate ranged from 0.7 to 40.2 %, with the highest found in western Saudi Arabia. PCR-fingerprinting results suggested that yeast migration was common among the geographic regions within each country. However, local climatic conditions can significantly impact yeast diversity at the local and continental levels.