The Secret Life of Proteins: Identifying the First Substrates of the Protease ClpYQ

Faculty of Science
Chemistry and Biomolecular Sciences
Taylor Lanosky
Proteins are a vital part of living organisms. In humans, they serve as building blocks of muscles, cartilage, bones, and skin.

Similarly, bacterial proteins are the core of all cellular processes allowing bacteria to survive. Regulating the levels of these proteins is crucial to ensure optimal cell function and ultimately survival of the organism. Protein levels are primarily controlled through proteases – enzymes that break down proteins to allow their digestion and absorption.

Taylor Lanosky – an undergraduate student supervised by Professor Christopher Boddy – is investigating a particular protease known as ClpYQ. This ATP-dependant protease is one of six that are present in the bacteria Bacillus subtilis. Unlike other proteases, ClpYQ has not previously been characterized, making its structure, function, degradation pathways and substrates a complete mystery. Therefore, Taylor’s honours thesis aimed at identifying and characterizing the first substrates of ClpYQ to potentially target it using antibiotics. Armeniaspirol is an antibiotic known to target ClpYQ, preventing cell division and resulting in the death of the bacteria. However, the mechanism of action of armeniaspirolon ClpYQ is also unknown, making it another focus of Taylor’s research.

Taylor utilized numerous biochemical techniques, such as cloning, protein purification, in vitro and in vivo degradation assays, Bacillus subtilis transformations, and collection of minimum inhibitory concentration data for armeniaspirol. These methods allowed her to identify the first two substrates of ClpYQ, namely the proteins DivIVA and Mbl. Through unexpected results, she demonstrated that DivIVA and Mbl are also substrates for another ATP-dependant protease, ClpXP. DivIVA appears to be essential for cell division, while Mbl plays a crucial role in cell elongation. Taylor observed that an excess of either substrate led to cell division arrests and bacterial death. Thus, she demonstrated that armeniaspirol targets ClpYQ and inhibits the degradation of DivIVA and Mbl, ultimately leading to cell death.

In addition to publishing her results in RSC Medicinal Chemistry and the Journal of Organic Chemistry, Taylor is working on four additional research papers. She is a member of the NASA Microbes Analysis Working group, where she analyses results from experiments conducted at the NASA space station. An emerging scientist, Taylor is applying for PhD programs to pursue her passion for space and biochemistry.

Taylor values the opportunities, trust and support received from her supervisor Prof. Boddy and PhD student Michael Darnowski. She urges other students to do the things that they’re scared of and to put themselves out of their comfort zone as this might lead to new and exciting paths.

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