A food color based colorimetric assay for Cryptococcus neoformans laccase activity.
A food color based colorimetric assay for Cryptococcus neoformans laccase activity.
复制标题
基于食品颜色的新型隐球菌漆酶活性比色测定。
DOI：
10.1101/2024.01.01.573823
复制
发表时间：
2024
期刊：
影响因子：
--
通讯作者：
Casadevall,Arturo
中科院分区：
文献类型：
--
作者：
Ramirez,LiaSanchez;Dragotakes,Quigly;Casadevall,Arturo
Cryptococcus neoformansis a fungal pathogen that causes cryptococcosis primarily in immunocompromised patients, such as those with HIV/AIDS. One survival mechanism ofC. neoformansduring infection is melanin production, which catalyzed by laccase and protects fungal cells against immune attack. Hence, the comparative assessment of laccase activity is useful for characterizing cryptococcal strains. We serendipitously observed that culturingC. neoformanswith food coloring resulted in degradation of some dyes with phenolic structures. Consequently, we investigated the color changes for the food dyes metabolized byC. neoformanslaccase and by using this effect explored the development of a colorimetric assay to measure laccase activity. We developed several versions of a food dye-based colorimetric laccase assay that can be used to compare the relative laccase activities between differentC. neoformansstrains. We found that phenolic color degradation was glucose-dependent, which may reflect changes in the reduction properties of the media. Our food color-based colorimetric assay has several advantages, including lower cost, irreversibility, and not requiring constant monitoring , over the commonly used 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay for determining laccase activity. This method has potential applications to bioremediation of water pollutants in addition to its use in determining laccase virulence factor expression.IMPORTANCECryptococcus neoformansis present in the environment, and while infection is common, disease occurs mostly in immunocompromised individuals.C. neoformansinfection in the lungs results in symptoms like pneumonia, and consequently, cryptococcal meningitis occurs if the fungal infection spreads to the brain. The laccase enzyme catalyzes the melanization reaction that serves as a virulence factor forC. neoformans. Developing a simple and less costly assay to determine the laccase activity inC. neoformansstrains can be useful for a variety of procedures ranging from studying the relative virulence of cryptococci to environmental pollution studies.
