A comparison of the enzymatic properties of three recombinant isoforms of thrombolytic and antibacterial protein — destabilase-lysozyme from medicinal leech
Biochemical characterization published in BMC Biochemistry (2015)
Abstract
BACKGROUND: Destabilase-Lysozyme (mlDL) is a multifunctional i-type enzyme that has been found in the secretions from the salivary glands of medicinal leeches. mlDL has been shown to exhibit isopeptidase, muramidase and antibacterial activity. This enzyme attracts interest because it expresses thrombolytic activity through isopeptidolysis of the ε-(γ-Glu)-Lys bonds that cross-link polypeptide chains in stabilised fibrin. To date, three isoforms of mlDL have been identified. The enzymatic properties of pure mlDL isoforms have not yet been described because only destabilase complexes containing other proteins could be isolated from the salivary gland secretion and because low product yield from the generation of recombinant proteins has made comprehensive testing difficult. RESULTS: In the present study, we optimised the procedures related to the expression, isolation and purification of active mlDL isoforms (mlDL-Ds1, mlDL-Ds2, mlDL-Ds3) using an Escherichia coli expression system, and we detected and compared their muramidase, lytic, isopeptidase and antimicrobial activities. After optimisation, the product yield was 30 mg per litre of culture. The data obtained in our study led to the suggestion that the recombinant mlDL isoforms isolated from inclusion bodies form stable oligomeric complexes. Analyses of the tested activities revealed that all isoforms exhibited almost identical patterns of pH and ionic strength effects on the activities. We determined that mlDL-Ds1, 2, 3 possessed non-enzymatic antibacterial activity independent of their muramidase activity. For the first time, we demonstrated the fibrinolytic activity of the recombinant mlDL and showed that only intact proteins possessed this activity, suggesting their enzymatic nature. CONCLUSIONS: The recombinant Destabilase-Lysozyme isoforms obtained in our study may be considered potential thrombolytic agents that act through a mechanism different from that of common thrombolytics.
Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.
Summary
Comparative enzymatic characterization of three recombinant destabilase-lysozyme isoforms from H. medicinalis. Isoforms differ in lysozyme activity but conserve isopeptidase function.
Why This Matters for Hirudotherapy
This research optimized the expression, isolation, and purification of three recombinant isoforms of destabilase-lysozyme (mlDL) from the medicinal leech using an E. coli system to compare their enzymatic properties. The study confirmed that all three isoforms possess muramidase, antibacterial, and fibrinolytic activities, with the latter being enzymatic and dependent on intact protein structure. This is relevant to ASH as it thoroughly characterizes the specific functional profiles of different leech secretome components, reinforcing their potential as thrombolytic and antibacterial agents. However, the scope is strictly limited to in vitro biochemical characterization, offering no in vivo or clinical validation.
Citation
A comparison of the enzymatic properties of three recombinant isoforms of thrombolytic and antibacterial protein — destabilase-lysozyme from medicinal leech.
Kurdyumov AS et al. · BMC biochemistry, 2015
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