The spontaneous host-range mutants 812F1 and K1/420 are derived from polyvalent phage 812 that is almost identical to phage K, belonging to family Myoviridae and genus Kayvirus. Phage K1/420 is used for the phage therapy of staphylococcal infections. Endolysin of these mutants designated LysF1, consisting of an N-terminal cysteine-histidine-dependent aminohydrolase/peptidase (CHAP) domain and C-terminal SH3b cell wall-binding domain, has deleted middle amidase domain compared to wild-type endolysin. In this work, LysF1 and both its domains were prepared as recombinant proteins and their function was analyzed. LysF1 had an antimicrobial effect on 31 Staphylococcus species of the 43 tested. SH3b domain influenced antimicrobial activity of LysF1, since the lytic activity of the truncated variant containing the CHAP domain alone was decreased. The results of a co-sedimentation assay of SH3b domain showed that it was able to bind to three types of purified staphylococcal peptidoglycan 11.2, 11.3, and 11.8 that differ in their peptide bridge, but also to the peptidoglycan type 11.5 of Streptococcus uberis, and this capability was verified in vivo using the fusion protein with GFP and fluorescence microscopy. Using several different approaches, including NMR, we have not confirmed the previously proposed interaction of the SH3b domain with the pentaglycine bridge in the bacterial cell wall. The new naturally raised deletion mutant endolysin LysF1 is smaller than LysK, has a broad lytic spectrum, and therefore is an appropriate enzyme for practical use. The binding spectrum of SH3b domain covering all known staphylococcal peptidoglycan types is a promising feature for creating new chimeolysins by combining it with more effective catalytic domains.
- MeSH
- endopeptidasy genetika izolace a purifikace metabolismus MeSH
- hostitelská specificita * MeSH
- mutantní proteiny genetika izolace a purifikace metabolismus MeSH
- Myoviridae enzymologie genetika fyziologie MeSH
- peptidoglykan metabolismus MeSH
- proteinové domény MeSH
- sekvenční delece * MeSH
- Staphylococcus virologie MeSH
- vazba proteinů MeSH
- Publikační typ
- časopisecké články MeSH
Rhomboid proteases are intramembrane enzymes that hydrolyze peptide bonds of transmembrane proteins in the lipid bilayer. They play a variety of roles in key biological events and are linked to several disease states. Over the last decade a great deal of structural and functional knowledge has been generated on this fascinating class of proteases. Both structural and kinetic analyses require milligram amounts of protein, which may be challenging for membrane proteins such as rhomboids. Here, we present a detailed protocol for optimization of expression and purification of three rhomboid proteases from Escherichia coli (ecGlpG), Haemophilus influenzae (hiGlpG), and Providencia stuartii (AarA). We discuss the optimization of expression conditions, such as concentration of inducing agent, induction time, and temperature, as well as purification protocol with precise details for each step. The provided protocol yields 1-2.5mg of rhomboid enzyme per liter of bacterial culture and can assist in structural and functional studies of intramembrane proteases.
- MeSH
- DNA vazebné proteiny biosyntéza chemie genetika izolace a purifikace MeSH
- endopeptidasy biosyntéza chemie genetika izolace a purifikace MeSH
- Escherichia coli enzymologie MeSH
- Haemophilus influenzae enzymologie MeSH
- kinetika MeSH
- lipidové dvojvrstvy chemie MeSH
- membránové proteiny biosyntéza chemie genetika izolace a purifikace MeSH
- molekulární biologie metody MeSH
- proteiny z Escherichia coli biosyntéza chemie genetika izolace a purifikace MeSH
- Providencia enzymologie MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Publikační typ
- časopisecké články MeSH
Rhomboids are ubiquitous intramembrane serine proteases that are involved in various signaling pathways. This fascinating class of proteases harbors an active site buried within the lipid milieu. High-resolution structures of the Escherichia coli rhomboid GlpG with various inhibitors revealed the catalytic mechanism for rhomboid-mediated proteolysis; however, a quantitative characterization was lacking. Assessing an enzyme's catalytic parameters is important for understanding the details of its proteolytic reaction and regulatory mechanisms. To assay rhomboid protease activity, many challenges exist such as the lipid environment and lack of known substrates. Here, we summarize various enzymatic assays developed over the last decade to study rhomboid protease activity. We present detailed protocols for gel-shift and FRET-based assays, and calculation of KM and Vmax to measure catalytic parameters, using detergent solubilized rhomboids with TatA, the only known substrate for bacterial rhomboids, and the model substrate fluorescently labeled casein.
- MeSH
- buněčná membrána enzymologie MeSH
- DNA vazebné proteiny chemie izolace a purifikace metabolismus MeSH
- endopeptidasy chemie izolace a purifikace metabolismus MeSH
- enzymatické testy metody MeSH
- Escherichia coli enzymologie MeSH
- katalytická doména MeSH
- membránové proteiny chemie izolace a purifikace metabolismus MeSH
- proteiny z Escherichia coli chemie izolace a purifikace metabolismus MeSH
- proteolýza * MeSH
- substrátová specifita MeSH
- vazba proteinů MeSH
- vztahy mezi strukturou a aktivitou MeSH
- Publikační typ
- časopisecké články MeSH
- MeSH
- endopeptidasy biosyntéza izolace a purifikace metabolismus MeSH
- gag-pol fúzové proteiny biosyntéza izolace a purifikace metabolismus MeSH
- geny gag MeSH
- geny pol MeSH
- virus ptačí myeloblastózy enzymologie genetika MeSH
- viry ptačího sarkomu enzymologie genetika MeSH
- Publikační typ
- srovnávací studie MeSH
- Klíčová slova
- FLOBUFEN (GALENA, OPAVA) ČR,
- MeSH
- antiflogistika nesteroidní farmakologie MeSH
- chromatografie afinitní MeSH
- endopeptidasy izolace a purifikace MeSH
- hodnocení léčiv MeSH
- lidé MeSH
- synoviální tekutina chemie MeSH
- tetracyklin farmakologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- srovnávací studie MeSH
An extracellular proteinase from Enterococcus faecalis subsp. liquefaciens has been purified 780-fold by a method including gel filtration on Sephadex G-50 and affinity chromatography with gramicidin J as ligand. Approximately 15% of the original enzyme activity was recovered. A purification of 14,800-fold, with 11.4% yield, may be reached using chromatofocusing as final step in the purification procedure. The molar mass of the enzyme has been estimated to be approximately 30 kDa by Sephadex gel filtration and approximately 26 kDa by SDS-PAGE. The isoelectric point has been found to be 4.6. Maximum enzyme activity of the proteinase has been observed at pH 7.5 and 45 degrees C. The enzyme hydrolyzed bovine serum albumin, alpha-lactoalbumin, beta-lactoglobulin, casein and pork myofibrillar and sarcoplasmic proteins. The extracellular proteinase was very stable; the enzyme maintained its activity in cell-free extracts over a very wide range of temperatures (-25 to 37 degrees C) for at least 2 months. At 12 degrees C, it was stable in the pH range of 5.5 to 8.0.
- MeSH
- chromatografie afinitní MeSH
- endopeptidasy chemie izolace a purifikace MeSH
- Enterococcus faecalis enzymologie izolace a purifikace MeSH
- extracelulární prostor enzymologie MeSH
- gelová chromatografie MeSH
- izoelektrický bod MeSH
- koncentrace vodíkových iontů MeSH
- molekulová hmotnost MeSH
- potravinářská mikrobiologie MeSH
- potravinářská technologie MeSH
- stabilita enzymů MeSH
- sýr mikrobiologie MeSH
- Publikační typ
- časopisecké články MeSH
