Fungal lipases

In order to enhance the potential of synthetic reactions of lipids and the transesterification in organic solvents, a fungal lipase from Phycomyces nites was chemically modified. The promotion of dispersibility in orgaiuc solvents resulted in a much higher reactivity. Chemically modified lipases showed higher reactivity than unmodified lipase when they were utilized for the transesterification of triglycerides and other lipids. The initial rate of transesterification in organic solvents by modified lipase was 40 times faster than that of unmodified lipase. Chemically modified lipase was also found applicable for the syndesis of other fatty acids esters. 

In general, a fungal lipase from Phycomyces nites catalyzed the hydrolysis of lipids... 

The biotechnological production of flavour compounds is particularly focused on esters and lactones. Lipase from Mucor miehei is the most widely studied fungal lipase [30-35]. Esters of acids from acetic acid to hexanoic acid and alcohols from methanol to hexanol, geraniol and citronellol have been synthesised using lipases from Mucor miehei, Aspergillus sp., Candida rugosa, Rhizopus arrhizus and Trichosporum fermentans [32-37]. 

The three dimensional structures of human pancreatic Lipase and Rhizo-mucor miehei lipase have recently been elucidated 1141-1431. Among the lipases purified foam different sources—mammals, bacteria, fungi, and plants-—the fungal lipases from Rhizopuj species exhibit a remarkably broad pH zone of stability and activity, extending from pH 3 to 9. 

As in fungal lipases, the catalytic center is not accessible to solvent. However, instead of a simple helical lid found in RmL, or two lids seen in GcL, hPL appeared to have several loops that collectively obscure the entrance to the active site. It was subsequently observed that the displacement of two of these leads to the enzyme assuming an active conformation (van Tilbeurgh et al., 1993). One of these loops is a surface loop between residues 237 and 261, both of which are cysteines linked by a disulfide bridge. The second fragment is a shorter loop spanning residues 78 and 84. 

Brzozowski, A. M., Derewenda, U., Derewenda, Z. S., Dodson, G. G., Lawson, D. M., Turkenburg, j. P., Bjorkling, F., Huge-jensen, B., Patkar,S. A.,andThim, L. (1991). A model for interfacial activation in lipases from the structure of a fungal lipase-inhibitor complex. Nature (London) 351, 491-494. 

J.A. Contreras, M. Karlsson, T. Osterlund, H. Laurell, a. Svensson, and C. Holm, Hormone-sensitive lipase is structurally related to acetylcholinesterase, bile salt-stimulated lipase, and several fungal lipases building of a three-dimensional model for the catalytic domain of hormone-sensitive lipase, J. Biol. Chem., 1996, 273, 31426-31430. 

Figure 5 Stability in function of pH of pancreatin lipase (broken line) compared with a fungal lipase (Rhizopus javanicus) (solid line). The pancreatin lipase was incubated for 3 hours at 37°C and the fungal lipase for 4 hours. After the preincubation period the activity was measured using the FIP procedure.

Lipolase. [NovoNordisk] Fungal lipase for det ents, laundry powds., pre-spotters. 

Several different types of compounds have been shown to be produced, of which several types may be related to common metabolic pathways. Thus, free fatty acids may be first released as a result of fungal lipase activity. These fatty acids may be oxidized to keto-acids, subsequently being deearboxylated to methyl ketones followed by reduction to secondary alcohols (Hawke, 1966). Different mold fungi possess different types of lipases, which may give rise to clusters of different compounds. Unsaturated fatty acids may be transformed to volatile aldehydes, alcohols and esters by hydroperoxidation by lipoxygenase aetivity (Eriksson, 1974). 

Brzozowski AM, Derewenda U, Derewenda ZS, Dodson G, Lawson D, Turkenburg IP (1991) A model for interfacial activation in lipases from the structure of a fungal lipase-inhibitor complex. Nature 351 491 94... 

Ramarethinam, S., K. Latha, and N. Rajalakshmi. 2002. Use of a Fungal Lipase for Enhancement of Aroma in Black Tea. Food Science and Technology Research 8 (4) 328-332. 

Singh, A., and M. Mukhopadhyay. 2011. Overview of Fungal Lipase A Review. Applied Biochemistry and Biotechnology 166 (2) 486-520. 

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