The hyphae of Aspergillus ustus mold can function and grow at more than 1000 m below sea level by adopting a micro-spherical shape.

Even though they are at home on dry land, Aspergillus ustus mold is also capable of living, growing, and reproducing under more than 1000 meters of water. Man-made machines have to be specially and painstakingly designed to function at those crushing depths, but Aspergillus ustus does so by adopting a micro-spheroid shape. Production and release of enzymes for breaking down their food functions well at these depths and cold temperatures as well.


"Two species of filamentous fungi, Aspergillus ustus (Bain.) Them & Church and Graphium sp., were isolated from calcareous animal shells at depths of 860 m in the Arabian Sea and 965 m in the Bay of Bengal…The results indicate barotolerance of terrestrial species of fungi and suggest that they might be active under deep-sea conditions." (Raghukumar and Raghukumar 1998:153)

"Synthesis of protease was evident at 100 bar pressure in both the test fungi at 30 as well as 10°C." (Raghukumar and Raghukumar 1998: 155)

"Calcareous shells have an organic matrix of conchyolin, a horny protein which is known to be used by endolithic fungi as a nutrient source (Alderman 1976). In light of this, synthesis and activity of protease under pressure and at low temperature are of great significance to these endolithic deep-sea fungi for survival." (Raghukumar and Raghukumar 1998: 161)

"Extensive fungal borings of calcium carbonate sediments have also been described from 210 to 1450 m in Bahamian waters." (Raghukumar C. and S. 1998:157)

"Spherical cells might be an adaptation by these fungi for pressure tolerance. Beaded hyphal structures, as observed in natura! samples, were also observed under simulated laboratory conditions." (Raghukumar and Raghukumar 1998:160)

Journal article
Barotolerance of fungi isolated from deep-sea sediments of the Indian OceanAquat. Microb. Ecol.April 9, 2007
C Raghukumar, S Raghukumar