Team:Calgary/Project/OurSensor/Reporter/BetaLactamase

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Beta-Lactamase

What is Beta-lactamase?

Beta-lactamase (BLA) is an enzyme encoded by the ampicillin resistant gene (ampr), frequently present in plasmids for selection. Structurally, beta-lactamase is a 29-kDa monomeric enzyme (figure 1). Its enzymatic activity provides resistance to beta-lactam antibiotics such as cephamysin, carbapenems and penicillin through hydrolysis of the β-lactam ring, a structure shared by these antibiotics (Qureshi, 2007).

ADD 3D STRUTURE OF BLAC

Figure 1. 3D structure of beta-lactmase obtained from our team’s work in Autodesk Maya. To learn more about our modeling, clickhere.

Many advantages come from working with beta-lactamase. It shows high catalytic efficiency and simple kinetics. Also, no orthologs of BLA are known to be encoded by eukaryotic cells and no toxicity was identified making this protein very useful in studies involved eukaryotes (Qureshi, 2007). Beta-lactamase has been used to track pathogens in infected murine models (Kong et. al, 2010). However, in addition to its application in eukaryotic cells, beta-lactamase efficiently cleaves a wide variety of substrates but its versatility goes beyond that; BLA preserves its activity even when fused to heterologous protein (Moore et. al, 1996). This feature, in particular, makes a potential tool for assemble of synthetic constructs. We retrieved the beta-lactamase gene from the backbone of the pSB1A3 plasmid and added a His-tag to it. We also fused a flexible glycine linker (BBa_K157013) to the N-terminus of BLA so we could later connected to our detector. More details on how these procedures were done can be found at our Reporter Journal.