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Kinetic Screening of Nuclease Activity using Nucleic Acid Probes
Published on: November 1, 2019
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Probing for actinase activity of protealysin
O A Tsaplina1, T N Efremova, L V Kever
1Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russia.
Biochemistry. Biokhimiia
|August 4, 2009
Summary
Protealysin, a bacterial metallopeptidase, cleaves actin and activates matrix metalloprotease MMP2. This actinase activity may facilitate bacterial invasion of eukaryotic cells, as observed with Serratia proteamaculans 94.
Area of Science:
- Microbiology
- Biochemistry
- Cell Biology
Background:
- Serratia proteamaculans 94 produces protealysin, a thermolysin-like metallopeptidase.
- Bacterial metalloproteases are implicated in host-pathogen interactions.
Purpose of the Study:
- To investigate the enzymatic activity of protealysin on actin and matrix metalloprotease MMP2.
- To explore the role of protealysin in the invasion of eukaryotic cells by S. proteamaculans 94.
Main Methods:
- Proteolytic assays using globular actin and proMMP2.
- Zymography to assess MMP2 activation.
- Incubation of S. proteamaculans 94 with human larynx carcinoma Hep-2 cells.
Main Results:
- Protealysin cleaves specific peptide bonds in actin, producing a resistant 36 kDa fragment.
- Protealysin activates proMMP2 to its mature 66 kDa form.
- S. proteamaculans 94 was detected within Hep-2 cells, indicating bacterial invasion.
Conclusions:
- Protealysin exhibits actinase activity and activates MMP2.
- The actinase activity of bacterial metalloproteases may contribute to bacterial invasion.
- S. proteamaculans 94 demonstrates the capacity to invade eukaryotic cells.
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