Phosphate solubilization by Antarctic yeasts isolated from lichens

Area of Science:

• Microbiology
• Biotechnology
• Environmental Science

Background:

• Antarctica harbors diverse microorganisms with biotechnological potential.
• Knowledge regarding yeasts with phosphate solubilization activity in Antarctica is limited.
• Phosphate solubilization is crucial for nutrient availability in ecosystems.

Purpose of the Study:

• To evaluate the in vitro phosphate solubilization ability of yeasts isolated from Antarctic lichens.
• To identify yeast genera and specific isolates with high phosphate solubilization activity.
• To investigate the organic acids involved in the phosphate solubilization process.

Main Methods:

• Screening of 147 yeast isolates on solid NBRIP medium at 15°C.
• Selection of promising strains for phosphate solubilization assays in liquid medium at 25°C and 30°C.
• Analysis of organic acids produced during solubilization using High-Performance Liquid Chromatography (HPLC).

Main Results:

• 43 out of 147 (29%) yeast isolates exhibited phosphate solubilization.
• Vishniacozyma and Cystobasidium were the most prevalent genera with positive activity.
• Two strains, Vishniacozyma victoriae 2.L15 and an unidentified A.L6 strain, showed significant phosphate solubilization, producing up to 619.04 mg/L and 31.25 mg/L of phosphate, respectively.
• Tartaric and acetic acids were detected as major organic acids contributing to phosphate solubilization.

Conclusions:

• Antarctic lichen-associated yeasts possess considerable phosphate solubilization potential.
• Vishniacozyma victoriae and other unidentified yeasts are promising candidates for biotechnological applications.
• Further research into the genetic and proteomic mechanisms of phosphate solubilization is warranted.