Unlocking the potential of a thermophilic fungus

Thermostable enzymes are of special industrial interest and have considerable importance in the multibillion dollar biotechnology industry due to their robustness and suitability to harsh processing conditions. The thermophilic compost-dwelling fungus Thermomyces lanuginosus is an attractive source of various thermostable enzymes including cellulase-free thermostable xylanase, β-xylosidase, α-galactosidase, lipase, α–amylase, glucoamylase, mannanase, pectinase and other enzymes with potential applications in various industries. Recent genome sequencing of this xylanase superproducer by our group has opened a unique opportunity to identify, isolate and specifically engineer enzymes out of a total of 5,105 protein-coding genes. This includes a large number of industrially relevant enzymes involved in bioremediation and biodegradation, carbon- and nitrogen-fixation, fatty-acid synthesis, energy-production and other metabolic pathways. The fungus when cultivated on corn cobs secreted a total of 74 proteins, including nine glycoside hydrolases, a lipase and amylase. Interestingly, the secretome also revealed the presence of unexplored enzymes such as glutaminase, fructose-bisphosphate aldolase and cyanate hydratase, which are of major industrial significance. Additionally, we have shown the importance of two thermostable chitinases (Chit1 and Chit2) in producing chitobiose from the shrimp shell waste. Work is underway on phytases from this fungus for plant-growth promotion, amelioration in bioethanol production and in improving nutritional characteristics of a local non-alcoholic beverage, Mageu. More recently, the role of its carbonic anhydrase in biomimetic CO₂ sequestration is also being investigated. Overall, T. lanuginosus can be regarded as an enzyme factory having potential to produce several industrial enzymes with a myriad of commercial and environmental applications.