LAUSR

A simple and rapid method to detect extracellular protease produced by fungi is described. This method is more sensitive than the conventional agar plate method and could be used for screening a large number of samples in a short time. It also enables the visualization of different types of proteases. This method could be used with suitable modifications to detect other extracellular enzymes. Keywords– Agar plate assay– enzyme assay –fungal enzymes – fungal protease Introduction Fungal proteases are used in the food, dairy, detergent, leather and pharmaceutical industries. They are also used for bioremediation and production of therapeutic peptides (Wu et al. 2006, Yike 2011). Fungal enzymes are more suited for industrial applications as fungi are easily cultured and are fast growing; many fungal enzymes are extracellular and are amenable to manipulations. Furthermore, fungal proteases are more diverse and exhibit wider substrate specificity (Kudryavtseva et al. 2008). Apart from engineering known enzymes for better efficiency by methods including directed evolution and rational design, screening microbes from relatively unexplored ecological niches for novel enzymes with desirable properties is a common method for improving the current industrial enzyme scenario (Kumar et al. 2011, Li et al. 2012). Fungal endophytes are non-disease causing endosymbionts of plants and comprise a group of different lineages (Guo et al. 2001, Hyde & Soytong 2008). Numerous studies have denoted the potential of endophytes to produce secondary metabolites exhibiting different bioactivities (Suryanarayanan et al. 2009, Kaushik et al. 2014, Mohana Kumara et al. 2014, Chen et al. 2016). Enzymes are produced in nature by endophytic fungi (Promputtha et al. 2010), yet they have not been explored intensively for their enzyme range (Suryanarayanan et al. 2012). Using endophytes, we describe here a simple and rapid qualitative assay for secreted fungal proteases.