Viability and molecular authentication of Coccidioides spp. isolates from the Instituto de Medicina Tropical de São Paulo culture collection, Brazil

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: Sarah Desirée Barbosa Cavalcanti, Mônica Scarpelli Martinelli Vidal, Maria da Glória Teixeira de Sousa, Gilda Maria Barbaro Del Negro
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 2013
• Subjects: Culture collection; Coccidioides; Viability; Molecular identification; Long-term preservation; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1590/S0036-46652013000100002; https://doaj.org/article/37b073a6f4ac456eb6132809380281f7

Coccidioidomycosis is an emerging fungal disease in Brazil; adequate maintenance and authentication of Coccidioides isolates are essential for research into genetic diversity of the environmental organisms, as well as for understanding the human disease. Seventeen Coccidioides isolates maintained under mineral oil since 1975 in the Instituto de Medicina Tropical de São Paulo (IMTSP) culture collection, Brazil, were evaluated with respect to their viability, morphological characteristics and genetic features in order to authenticate these fungal cultures. Only five isolates were viable after almost 30 years, showing typical morphological characteristics, and sequencing analysis using Coi-F and Coi-R primers revealed 99% identity with Coccidioides genera. These five isolates were then preserved in liquid nitrogen and sterile water, and remained viable after two years of storage under these conditions, maintaining the same features.