METHANOL RESISTANCE BACTERIAL LIPASE FROM PHYLLOSPHERE BACTERIA – IDENTIFICATION AND INSIGHT INTO BASE OF RESISTANCE

Lipases are enzymes that catalyze the hydrolysis of fats with many industrial applications. One much sought-after application is the production of biodiesel from waste fats, but this application is hampered by the scarcity of methanol resistance lipases, currently coming from handful of organisms, mostly such from (remote) extreme environments, making their isolation and study complex and expensive.

Plant areal parts (e.g. leaves and fruits) offer one of the largest bio-available surfaces areas for microbial colonization. Furthermore, this habitat is often exposed to extreme weather change, high UV irradiation and low water availability but very rich in lipids. To-date, the majority of research held in phyllosphere microbiology focused on study of specific plant pathogen or microbial community structure, but from industrial point of view, this habitat is still a "Newfoundland".

In our research, we are utilizing the phyllosphere bacterial population as a source for lipase producing bacterial species, searching to methanol producing lipases. In our screening, over 25% of the bacteria isolated (151 total) expressed lipases capable of digesting long chain fatty acids triglycerides, and at-least one of these isolates
(P. stutzeri SBW10) produced a lipase active in the presence of 60% methanol.

Sequence homology of methanol resistance and sensitive lipases from our isolates suggest that small number of amino acids could be enough to provide methanol resistance.

In summery our findings demonstrate that the phyllosphere habitat can be a useful source for industrial applicable enzymes and that a small number of amino acid substitutes could probably provide for methanol resistance.

Predicted 3D structure of the P. stutzeri SBW10 methanol resistance lipase