scholarly journals β-Lytic Protease of Lysobacter capsici VKM B-2533T

Antibiotics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 744
Author(s):  
Alexey S. Afoshin ◽  
Mihail A. Konstantinov ◽  
Ilya Yu. Toropygin ◽  
Irina V. Kudryakova ◽  
Natalia V. Vasilyeva
Keyword(s):  
Antimicrobial Agents ◽  
Biochemical Characterization ◽  
Micrococcus Luteus ◽  
Culture Liquid ◽  
Living Cells ◽  
Peptide Bonds ◽  
Protein Substrates ◽  
Proteolytic Activities ◽  
Proteolytic Action ◽  
New Generation

Bacteriolytic enzymes are promising antimicrobial agents for developing new-generation drugs. Recently, we have isolated a β-lytic protease (BlpLc) from the culture liquid of Lysobacter capsici VKM B-2533T. This BlpLc possesses a valuable property, not described for β-lytic proteases (Blps) earlier, of hydrolyzing living cells of Staphylococcus aureus 55 MRSA clinical isolate. This work phylogenetically characterized the BlpLc and investigated its properties. Analysis revealed a variability of pre-/pro-parts of Blp precursors. The mature BlpLc is the closest to the earlier annotated but not isolated Blp from Lysobacter sp. Root690. The biochemical characterization found conditions for the BlpLc general bacteriolytic activity relative to autoclaved S. aureus 209P cells to differ from that of earlier isolated Blp. Unexpected was the effect of serine (phenylmethylsulfonyl fluoride (PMSF)) and cysteine (p-chloromercuribenzoate (p-CMB)) protease inhibitors on BlpLc bacteriolytic and proteolytic activities. The specificity of BlpLc proteolytic action relative to hemoglobin, elastin, gelatin, collagen, azofibrin, myoglobin, ovalbumin, and ovamucoid was found. New types of peptide bonds—Gly-X, Ser-X, Lys-X, Ala-X, Val-X, Glu-X, and Phe-X—hydrolyzed by the enzyme in protein substrates were first revealed using MALDI-TOF. Turbidimetrically, the BlpLc was found to lyze living cells of S. aureus 209P, Micrococcus luteus B1819, and M. roseus B1236, which is important for expanding the enzyme’s applied properties.

Biochemical characterization of human HIF hydroxylases using HIF protein substrates that contain all three hydroxylation sites

2011 ◽  
Vol 436 (2) ◽  
pp. 363-369 ◽  
Author(s):  
Melissa B. Pappalardi ◽  
Dean E. McNulty ◽  
John D. Martin ◽  
Kelly E. Fisher ◽  
Yong Jiang ◽  
...  
Keyword(s):  
Biochemical Characterization ◽  
Hypoxia Inducible Factor ◽  
Prolyl Hydroxylase ◽  
Transactivation Domain ◽  
Prolyl Hydroxylases ◽  
Proline Residue ◽  
Protein Substrates ◽  
Steady State Kinetic ◽  
Asparaginyl Hydroxylase

The HIF (hypoxia-inducible factor) plays a central regulatory role in oxygen homoeostasis. HIF proteins are regulated by three Fe(II)- and α-KG (α-ketoglutarate)-dependent prolyl hydroxylase enzymes [PHD (prolyl hydroxylase domain) isoenzymes 1–3 or PHD1, PHD2 and PHD3] and one asparaginyl hydroxylase [FIH (factor inhibiting HIF)]. The prolyl hydroxylases control the abundance of HIF through oxygen-dependent hydroxylation of specific proline residues in HIF proteins, triggering subsequent ubiquitination and proteasomal degradation. FIH inhibits the HIF transcription activation through asparagine hydroxylation. Understanding the precise roles and regulation of these four Fe(II)- and α-KG-dependent hydroxylases is of great importance. In the present paper, we report the biochemical characterization of the first HIF protein substrates that contain the CODDD (C-terminal oxygen-dependent degradation domain), the NODDD (N-terminal oxygen-dependent degradation domain) and the CAD (C-terminal transactivation domain). Using LC-MS/MS (liquid chromatography–tandem MS) detection, we show that all three PHD isoenzymes have a strong preference for hydroxylation of the CODDD proline residue over the NODDD proline residue and the preference is observed for both HIF1α and HIF2α protein substrates. In addition, steady-state kinetic analyses show differential substrate selectivity for HIF and α-KG in reference to the three PHD isoforms and FIH.

scholarly journals Oxazolidinone Antibiotics Target the P Site on Escherichiacoli Ribosomes

2002 ◽  
Vol 46 (4) ◽  
pp. 1080-1085 ◽  
Author(s):  
Hiroyuki Aoki ◽  
Lizhu Ke ◽  
Susan M. Poppe ◽  
Toni J. Poel ◽  
Elizabeth A. Weaver ◽  
...  
Keyword(s):  
Antimicrobial Agents ◽  
Wide Spectrum ◽  
Anaerobic Bacteria ◽  
Elongation Factor ◽  
Peptide Bond ◽  
23S Rrna ◽  
Peptide Bonds ◽  
A Site ◽  
Domain V ◽  
Trna Binding

ABSTRACT The oxazolidinones are a novel class of antimicrobial agents that target protein synthesis in a wide spectrum of gram-positive and anaerobic bacteria. The oxazolidinone PNU-100766 (linezolid) inhibits the binding of fMet-tRNA to 70S ribosomes. Mutations to oxazolidinone resistance in Halobacterium halobium, Staphylococcus aureus, and Escherichia coli map at or near domain V of the 23S rRNA, suggesting that the oxazolidinones may target the peptidyl transferase region responsible for binding fMet-tRNA. This study demonstrates that the potency of oxazolidinones corresponds to increased inhibition of fMet-tRNA binding. The inhibition of fMet-tRNA binding is competitive with respect to the fMet-tRNA concentration, suggesting that the P site is affected. The fMet-tRNA reacts with puromycin to form peptide bonds in the presence of elongation factor P (EF-P), which is needed for optimum specificity and efficiency of peptide bond synthesis. Oxazolidinone inhibition of the P site was evaluated by first binding fMet-tRNA to the A site, followed by translocation to the P site with EF-G. All three of the oxazolidinones used in this study inhibited translocation of fMet-tRNA. We propose that the oxazolidinones target the ribosomal P site and pleiotropically affect fMet-tRNA binding, EF-P stimulated synthesis of peptide bonds, and, most markedly, EF-G-mediated translocation of fMet-tRNA into the P site.

scholarly journals Assembly, Biochemical Characterization, Immunogenicity, Adjuvanticity, and Efficacy ofShigellaArtificial Invaplex

mSphere ◽  
2018 ◽  
Vol 3 (2) ◽  
pp. e00583-17 ◽  
Author(s):  
K. Ross Turbyfill ◽  
Kristen A. Clarkson ◽  
Anthony R. Vortherms ◽  
Edwin V. Oaks ◽  
Robert W. Kaminski
Keyword(s):  
Immune Response ◽  
Guinea Pigs ◽  
Biochemical Characterization ◽  
Diarrheal Disease ◽  
Protective Efficacy ◽  
Water Extract ◽  
Effective Vaccine ◽  
Oral Fluids ◽  
Specific Antigens ◽  
New Generation

ABSTRACTThe native Invaplex (InvaplexNAT) vaccine and adjuvant is an ion exchange-purified product derived from the water extract of virulentShigellaspecies. The key component of InvaplexNATis a high-molecular-mass complex (HMMC) consisting of theShigellalipopolysaccharide (LPS) and the invasin proteins IpaB and IpaC. To improve product purity and immunogenicity, artificial Invaplex (InvaplexAR) was developed using recombinant IpaB and IpaC proteins and purifiedShigellaLPS to assemble an HMMC consisting of all three components. Characterization of InvaplexARby various methods demonstrated similar characteristics as the previously reported HMMC in InvaplexNAT. The well-defined InvaplexARvaccine consistently contained greater quantities of IpaB, IpaC, and LPS than InvaplexNAT. InvaplexARand InvaplexNATimmunogenicities were compared in mouse and guinea pig dose escalation studies. In both models, immunization induced antibody responses specific for InvaplexNATand LPS while InvaplexARinduced markedly higher anti-IpaB and -IpaC serum IgG and IgA endpoint titers. In the murine model, homologous protection was achieved with 10-fold less InvaplexARthan InvaplexNATand mice receiving InvaplexARlost significantly less weight than mice receiving the same amount of InvaplexNAT. Moreover, mice immunized with InvaplexARwere protected from challenge with both homologous and heterologousShigellaserotypes. Guinea pigs receiving approximately 5-fold less InvaplexARcompared to cohorts immunized with InvaplexNATwere protected from ocular challenge. Furthermore, adjuvanticity previously attributed to InvaplexNATwas retained with InvaplexAR. The second-generationShigellaInvaplex vaccine, InvaplexAR, offers significant advantages over InvaplexNATin reproducibility, flexible yet defined composition, immunogenicity, and protective efficacy.IMPORTANCEShigellaspecies are bacteria that cause severe diarrheal disease worldwide, primarily in young children. Treatment of shigellosis includes oral fluids and antibiotics, but the high burden of disease, increasing prevalence of antibiotic resistance, and long-term health consequences clearly warrant the development of an effective vaccine. OneShigellavaccine under development is termed the invasin complex or Invaplex and is designed to drive an immune response to specific antigens of the bacteria in an effort to protect an individual from infection. The work presented here describes the production and evaluation of a new generation of Invaplex. The improved vaccine stimulates the production of antibodies in immunized mice and guinea pigs and protects these animals fromShigellainfection. The next step in the product’s development will be to test the safety and immune response induced in humans immunized with Invaplex.

scholarly journals DUF3380 Domain from a Salmonella Phage Endolysin Shows PotentN-Acetylmuramidase Activity

2016 ◽  
Vol 82 (16) ◽  
pp. 4975-4981 ◽  
Author(s):  
Lorena Rodríguez-Rubio ◽  
Hans Gerstmans ◽  
Simon Thorpe ◽  
Stéphane Mesnage ◽  
Rob Lavigne ◽  
...  
Keyword(s):  
Enzymatic Activity ◽  
Thermal Resistance ◽  
High Performance ◽  
Antimicrobial Agents ◽  
Biochemical Characterization ◽  
Specific Activity ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Gram Negative ◽  
Content Type

ABSTRACTBacteriophage-encoded endolysins are highly diverse enzymes that cleave the bacterial peptidoglycan layer. Current research focuses on their potential applications in medicine, in food conservation, and as biotechnological tools. Despite the wealth of applications relying on the use of endolysin, little is known about the enzymatic properties of these enzymes, especially in the case of endolysins of bacteriophages infecting Gram-negative species. Automated genome annotations therefore remain to be confirmed. Here, we report the biochemical analysis and cleavage site determination of a novelSalmonellabacteriophage endolysin, Gp110, which comprises an uncharacterizeddomain ofunknownfunction (DUF3380; pfam11860) in its C terminus and shows a higher specific activity (34,240 U/μM) than that of 14 previously characterized endolysins active against peptidoglycan from Gram-negative bacteria (corresponding to 1.7- to 364-fold higher activity). Gp110 is a modular endolysin with an optimal pH of enzymatic activity of pH 8 and elevated thermal resistance. Reverse-phase high-performance liquid chromatography (RP-HPLC) analysis coupled to mass spectrometry showed that DUF3380 hasN-acetylmuramidase (lysozyme) activity cleaving the β-(1,4) glycosidic bond betweenN-acetylmuramic acid andN-acetylglucosamine residues. Gp110 is active against directly cross-linked peptidoglycans with various peptide stem compositions, making it an attractive enzyme for developing novel antimicrobial agents.IMPORTANCEWe report the functional and biochemical characterization of theSalmonellaphage endolysin Gp110. This endolysin has a modular structure with an enzymatically active domain and a cell wall binding domain. The enzymatic activity of this endolysin exceeds that of all other endolysins previously characterized using the same methods. A domain of unknown function (DUF3380) is responsible for this high enzymatic activity. We report that DUF3380 hasN-acetylmuramidase activity against directly cross-linked peptidoglycans with various peptide stem compositions. This experimentally verified activity allows better classification and understanding of the enzymatic activities of endolysins, which mostly are inferred by sequence similarities. Three-dimensional structure predictions for Gp110 suggest a fold that is completely different from that of known structures of enzymes with the same peptidoglycan cleavage specificity, making this endolysin quite unique. All of these features, combined with increased thermal resistance, make Gp110 an attractive candidate for engineering novel endolysin-based antibacterials.

Protease activities of Acanthamoeba polyphaga and Acanthamoeba castellanii

2006 ◽  
Vol 52 (1) ◽  
pp. 16-23 ◽  
Author(s):  
José de Jesús Serrano-Luna ◽  
Isaac Cervantes-Sandoval ◽  
Jesús Calderón ◽  
Fernando Navarro-García ◽  
Victor Tsutsumi ◽  
...  
Keyword(s):  
Protease Activity ◽  
Serine Proteases ◽  
Biochemical Characterization ◽  
Acanthamoeba Castellanii ◽  
Cysteine Proteases ◽  
Skin Lesions ◽  
Sds Page ◽  
Serine Protease Family ◽  
Proteolytic Activities ◽  
Amoebic Keratitis

Acanthamoeba spp. are free-living amoebae that cause amoebic granulomatous encephalitis, skin lesions, and ocular amoebic keratitis in humans. Several authors have suggested that proteases could play a role in the pathogenesis of these diseases. In the present work, we performed a partial biochemical characterization of proteases in crude extracts of Acanthamoeba spp. and in conditioned medium using 7.5% SDS–PAGE copolymerized with 0.1% m/v gelatin as substrate. We distinguished a total of 17 bands with proteolytic activity distributed in two species of Acanthamoeba. The bands ranged from 30 to 188 kDa in A. castellanii and from 34 to 144 kDa in A. polyphaga. Additionally, we showed that the pattern of protease activity differed in the two species of Acanthamoeba when pH was altered. By using protease inhibitors, we found that the proteolytic activities belonged mostly to the serine protease family and secondly to cysteine proteases and that the proteolytic activities from A. castellanii were higher than those in A. polyphaga. Furthermore, aprotinin was found to in hibit crude extract protease activity on Madin–Darby canine kidney (MDCK) monolayers. These data suggest that protease patterns could be more complex than previously reported.Key words: Acanthamoeba spp., amoebic keratitis, serine proteases, cysteine proteases, cytopathic effect.

scholarly journals Biochemical characterization and genetic mapping of purine genes inMicrococcus luteus

1975 ◽  
Vol 26 (2) ◽  
pp. 163-171 ◽  
Author(s):  
Nirupama Mohapatra ◽  
Wesley E. Kloos
Keyword(s):  
Genetic Mapping ◽  
Reference Strain ◽  
Biochemical Characterization ◽  
Micrococcus Luteus ◽  
Growth Stimulation ◽  
Strain Atcc ◽  
Reciprocal Transformation ◽  
Marshall Test

SUMMARYPurine auxotrophs ofMicrococcus luteuswere induced byN-methyl-N′-nitro-N-nitrosoguanidine. They were biochemically characterized by growth stimulation with CO2-enriched air and purine intermediates and by the Bratton-Marshall test that is used to detect accumulated diazotizable amines. The mutants were divided into four classes:pur(EC),purH,purJ, andPur−. Thepur(EC) class was further subdivided intopurEandpurCby results of crossing all thepur(EC) mutants with a knownpurEreference strain (ATCC 27141). Mutants which were not linked to the referencepurEmarker were considered to bepurC. Genetic mapping was accomplished by using two-point reciprocal transformation crosses. The result of this study indicates thatpurJmutants may be loosely linked topurEandpurC, and purH mutants are not linked topurE,purCorpurJ.

scholarly journals Rheological and Antimicrobial Properties of Chitosan and Quinoa Protein Filmogenic Suspensions with Thyme and Rosemary Essential Oils

Foods ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1616
Author(s):  
Monserrat Escamilla-García ◽  
Raquel A. Ríos-Romo ◽  
Armando Melgarejo-Mancilla ◽  
Mayra Díaz-Ramírez ◽  
Hilda M. Hernández-Hernández ◽  
...  
Keyword(s):  
Essential Oils ◽  
Food Packaging ◽  
Antimicrobial Agents ◽  
Negative Impact ◽  
Micrococcus Luteus ◽  
Antimicrobial Properties ◽  
Antimicrobial Effect ◽  
Rheological Parameters ◽  
Force Microscopy ◽  
Synthetic Materials

Food packaging faces the negative impact of synthetic materials on the environment, and edible coatings offer one alternative from filmogenic suspensions (FS). In this work, an active edible FS based on chitosan (C) and quinoa protein (QP) cross-linked with transglutaminase was produced. Thyme (T) and rosemary (R) essential oils (EOs) were incorporated as antimicrobial agents. Particle size, Z potential, and rheological parameters were evaluated. The antimicrobial activity against Micrococcus luteus (NCIB 8166) and Salmonella sp. (Lignieres 1900) was monitored using atomic force microscopy and image analysis. Results indicate that EOs incorporation into C:QP suspensions did not affect the Z potential, ranging from −46.69 ± 3.19 mV to −46.21 ± 3.83 mV. However, the polydispersity index increased from 0.51 ± 0.07 to 0.80 ± 0.04 in suspensions with EO. The minimum inhibitory concentration of active suspensions against Salmonella sp. was 0.5% (v/v) for thyme and 1% (v/v) for rosemary. Entropy and fractal dimension of the images were used to confirm the antimicrobial effect of EOs, which modified the surface roughness.

Sign in / Sign up

Export Citation Format

Share Document