Hi I am Tim,

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My research focuses on the anaerobic degradation of n-alkanes, the primary components of natural gas and crude oil, which pose a significant ecological threat if released into the environment. Although energy-rich, their degradation is a major challenge due to the high stability of C-H and C-C bonds. The difficult initial activation step is catalyzed by, among others, methylalkylsuccinate synthases (Mas), a class of glycyl radical enzymes found in nitrate- and sulfate-reducing bacteria. These enzymes use a radical-based mechanism to add fumarate to the C2 position of n-alkanes, producing methylalkylsuccinates as the product.

I am particularly interested in the methylalkylsuccinate synthases found in the denitrifying strain Aromatoleum sp. HxN1 and the sulfate-reducing strain Desulfosarcine aeriophaga BuS5. The Mas complexes found in these two organisms consist of the four subunits (MasBCDE), forming a hetero-octamer. The large subunit MasD, that contains the active site, is characterized by a distinctive glycine and cysteine loop, which are essential for the reaction. 

The aim of my project is the isolation and subsequent structural and biochemical characterization of MasBCDE using different chromatographic techniques such as UPLC, IC and GC for substrate identification as well as Cryo-EM for structural analysis. Establishing a heterologous expression system for Mas enzymes will additionally allow the analysis of key mutations as well as the insertion process of the radial.