The present invention provides compositions and methods for assessing profiles of catalytically active enzymes in compositions containing a plurality of proteins. In preferred embodiments, the enzyme is a hydrolase, most preferably a cysteine protease. The methods described herein use activity based probes (“ABPs”) that have an affinity moiety for directing the binding of the ABP to one or more catalytically active target enzymes, a reactive group for forming a covalent bond at an active site of the target enzyme(s), and a TAG (e.g., a detectable label, preferably a fluorophore). One or more ABPs may be combined with a protein-containing sample under conditions for binding and reaction of the ABP(s) with target enzyme(s) that are present in the sample. The resulting products may then be used to assess the active enzyme profile of the sample, and can be correlated to the presence, amount, or activity of one or more target enzyme(s) present in the original complex protein mixture.
                            本发明提供了用于评估含有多种蛋白质的组合物中催化活性酶的剖面的组合物和方法。在优选实施例中,酶是一种
水解酶,最好是一种半胱
氨酸
蛋白酶。本文所述的方法使用活性基于探针(“ABP”),其具有亲和性基团,用于引导ABP与一个或多个催化活性靶酶的结合,具有反应性基团,用于在目标酶(s)的活性位点上形成共价键,以及一个标记(例如,可检测的标签,最好是荧光
染料)。一个或多个ABP可以与含有蛋白质的样品结合,在存在于样品中的目标酶的结合和反应条件下,与ABP(s)反应。然后可以使用所得的产物评估样品的活性酶剖面,并可以与原始复合蛋白质混合物中存在的一个或多个目标酶的存在,数量或活性相关联。