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2.
Nanoscale ; 13(32): 13658-13664, 2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34477641

RESUMO

Multiplexing methods which are capable of measurement of multiple analytes in a single assay are of great importance in many fields. The conventional strategy for simultaneous detection of multiple species is to construct a sensor array. Herein, we report an innovative multiplex multi-analyte detection platform in a non-array format for protease measurement. By monitoring protease degradation of a single peptide substrate containing two cleavage sites for a disintegrin and metalloproteinase 10 (ADAM10) and a disintegrin and metalloproteinase 10 (ADAM17) in a single nanopore, simultaneous detection and quantification of these two model proteases in mixture samples could satisfactorily be accomplished. Our developed multiplexing sensing platform has the potential to be coupled with the traditional sensor array to further improve the multiplexing capability of the sensor, which may find useful applications in clinical diagnosis and prognosis.


Assuntos
Técnicas Biossensoriais , Nanoporos , Endopeptidases , Peptídeo Hidrolases , Peptídeos
3.
Medicine (Baltimore) ; 100(35): e27162, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34477172

RESUMO

ABSTRACT: Cancer-associated fibroblasts (CAFs) have been attracting attention in recent years, but their nature has not been fully elucidated. Although CAFs have been recognized as an important therapeutic target, therapeutic agents have not been developed to date. CAFs are characterized by their high migration rate and involvement in epithelial-to-mesenchymal transition with some displaying a dendritic morphology that is reminiscent of fascin expression.The present study was designed to immunohistochemically investigate fascin expression in lung adenocarcinoma including CAFs and compare the results with existing CAF markers.We immunohistochemically investigated fascin expression in not only cancer tissue but also CAFs from 26 autopsy cases of lung adenocarcinoma. Immunohistochemistry of α-smooth muscle actin and fibroblast activation protein was also performed.Fascin-positive staining in CAFs was observed in all cases, with a strong correlation observed with existing CAF markers α-smooth muscle actin and fibroblast activation protein (P < .001). In addition, the proportion of tumor cells showing fascin-positive staining was found to correlate with its expression in CAFs (P < .05).We propose that CAFs express fascin, and that fascin may mediate crosstalk between cancer tissue and CAFs. Fascin might be a novel therapeutic target for treatments that target the cancer stroma.


Assuntos
Adenocarcinoma/metabolismo , Fibroblastos Associados a Câncer/metabolismo , Proteínas de Transporte/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas dos Microfilamentos/metabolismo , Actinas/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Endopeptidases/metabolismo , Feminino , Humanos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade
4.
J Microbiol ; 59(9): 840-847, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34383247

RESUMO

Endolysin, a peptidoglycan hydrolase derived from bacteriophage, has been suggested as an alternative antimicrobial agent. Many endolysins on staphylococcal phages have been identified and applied extensively against Staphylococcus spp. Among them, LysK-like endolysin, a well-studied staphylococcal endolysin, accounts for most of the identified endolysins. However, relatively little interest has been paid to LysKunlike endolysin and a few of them has been characterized. An endolysin LysSAP33 encoded on bacteriophage SAP33 shared low homology with LysK-like endolysin in sequence by 41% and domain composition (CHAP-unknown CBD). A green fluorescence assay using a fusion protein for LysSAP33_CBD indicated that the CBD domain (157-251 aa) was bound to the peptidoglycan of S. aureus. The deletion of LysSAP33_CBD at the C-terminal region resulted in a significant decrease in lytic activity and efficacy. Compared to LysK-like endolysin, LysSAP33 retained its lytic activity in a broader range of temperature, pH, and NaCl concentrations. In addition, it showed a higher activity against biofilms than LysK-like endolysin. This study could be a helpful tool to develop our understanding of staphylococcal endolysins not belonging to LysK-like endolysins and a potential biocontrol agent against biofilms.


Assuntos
Endopeptidases/metabolismo , Fagos de Staphylococcus/enzimologia , Staphylococcus aureus/virologia , Proteínas Virais/metabolismo , Sequência de Aminoácidos , Parede Celular/metabolismo , Parede Celular/virologia , Endopeptidases/química , Endopeptidases/genética , Peptidoglicano/metabolismo , Alinhamento de Sequência , Fagos de Staphylococcus/química , Fagos de Staphylococcus/genética , Fagos de Staphylococcus/fisiologia , Staphylococcus aureus/metabolismo , Proteínas Virais/química , Proteínas Virais/genética
5.
Food Res Int ; 147: 110461, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34399461

RESUMO

Salmonella enterica and Shiga toxin-producing (or verotoxin-producing) Escherichia coli are major foodborne pathogens, posing substantial food safety risks. Due to the negative effects of chemical treatment against foodborne pathogens, the application of enzyme-based techniques is currently receiving great attention. Here, we evaluated the inhibitory properties of Flavourzyme, a commercial peptidase, against these two foodborne pathogens. We noticed 4.0 and 5.5 log inhibition of biofilm formation by S. Typhimurium and E. coli, respectively, while treated with sub-minimum inhibitory concentrations of Flavourzyme for 24 h. For both bacteria, the enzyme exhibited quorum-quenching activity, preventing autoinducer-2 production completely by E. coli. In addition, Flavourzyme significantly suppressed the relative expression levels of biofilm-forming, quorum sensing, and virulence regulatory genes as measured by qRT-PCR. Based on our results, we suggest the use of Flavourzyme as a preventive agent against foodborne pathogens that possibly acts by inhibiting bacterial self-defense mechanisms following disruption of cellular proteins. This finding may shed light on how enzymes can be applied as a novel weapon to control foodborne illnesses to ensure food safety and public health.


Assuntos
Salmonella typhimurium , Escherichia coli Shiga Toxigênica , Biofilmes , Endopeptidases , Percepção de Quorum , Salmonella typhimurium/genética , Escherichia coli Shiga Toxigênica/genética , Virulência/genética
6.
Viruses ; 13(7)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34372584

RESUMO

Double-stranded DNA bacteriophages end their lytic cycle by disrupting the host cell envelope, which allows the release of the virion progeny. Each phage must synthesize lysis proteins that target each cell barrier to phage release. In addition to holins, which permeabilize the cytoplasmic membrane, and endolysins, which disrupt the peptidoglycan (PG), mycobacteriophages synthesize a specific lysis protein, LysB, capable of detaching the outer membrane from the complex cell wall of mycobacteria. The family of LysB proteins is highly diverse, with many members presenting an extended N-terminus. The N-terminal region of mycobacteriophage Ms6 LysB shows structural similarity to the PG-binding domain (PGBD) of the φKZ endolysin. A fusion of this region with enhanced green fluorescent protein (Ms6LysBPGBD-EGFP) was shown to bind to Mycobacterium smegmatis, Mycobacterium vaccae, Mycobacterium bovis BGC and Mycobacterium tuberculosis H37Ra cells pretreated with SDS or Ms6 LysB. In pulldown assays, we demonstrate that Ms6 LysB and Ms6LysBPGBD-EGFP bind to purified peptidoglycan of M. smegmatis, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis, demonstrating affinity to PG of the A1γ chemotype. An infection assay with an Ms6 mutant producing a truncated version of LysB lacking the first 90 amino acids resulted in an abrupt lysis. These results clearly demonstrate that the N-terminus of Ms6 LysB binds to the PG.


Assuntos
Bacteriólise/fisiologia , Micobacteriófagos/metabolismo , Proteínas Virais/genética , Membrana Celular/metabolismo , Parede Celular/metabolismo , Endopeptidases , Hidrólise , Mycobacterium/metabolismo , Mycobacterium/virologia , Peptidoglicano/metabolismo , Ligação Proteica
7.
Microb Pathog ; 160: 105137, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34390765

RESUMO

Chlamydia trachomatis urogenital tract infection causes pelvic inflammatory disease and infertility, increases the risk of co-infection with HPV and HIV. Chlamydial vaccination is considered the most promising approach to prevent and control its infection. Among various chlamydial vaccine candidates, chlamydial protease-like activity factor (CPAF) have been reported to provide robust protective immunity against genital chlamydial infection in mice with reduced vaginal shedding and oviduct pathology. However, CPAF is a serine protease which has enzymatical activity to degrade a large number of substrates. In order to increase the safety of CPAF vaccine, in this study, we used a mutant CPAF that is deficient in enzymatical activity to determine whether proteolytic activity of CPAF affect its vaccine efficacy. The wild type or mutant CPAF immunization causes a significant lower chlamydial shedding from the vaginal and resolve the infection as early as day 20, compared to day 28 in adjuvant control mice. More important, reduced upper reproductive tract pathology were also observed in these two groups. The mutant or wild type CPAF immunization induced not only robust splenic IFN-γ and serum IgG2a but also sIgA secretion in the vaginal fluids. Furthermore, neutralization of chlamydia with immune sera did not provide protection against oviduct pathology. However, adoptive transfer of CD4+ splenocytes isolated from the mutant or wild type CPAF immunized mice resulted in a significant and comparable reduced oviduct pathology. Our results indicate mutant CPAF vaccination is as same efficacy as wild type, and the protection relies on CD4+ T cells, which will further promote the development of CPAF as clinical chlamydial vaccine.


Assuntos
Infecções por Chlamydia , Chlamydia muridarum , Infecções do Sistema Genital , Administração Intranasal , Animais , Vacinas Bacterianas , Infecções por Chlamydia/prevenção & controle , Endopeptidases/genética , Feminino , Camundongos , Vacinação
8.
Microb Pathog ; 159: 105135, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34390766

RESUMO

Vibrio alginolyticus is a common opportunistic pathogen that can cause vibriosis of marine aquatic animals. The application of phages or particularly associated protein products for the treatment of vibriosis has shown prominent advantages compared with the treatment with traditional antibiotics. In this study, the function of a holin-endolysin system from V. alginolyticus phage HH109 was characterized by examining the effect of their overexpression on Escherichia coli and V. alginolyticus. Our data revealed that the endolysin of the phage HH109 has stronger bactericidal activity than the holin, as evidenced by observing more cell death and severe structural damage of cells in the endolysin-expressing E. coli. Furthermore, the two proteins displayed the synergistic effect when the holA and lysin were co-expressed in E. coli, although no interaction between them was detected using the bacterial two-hybrid assay. Transmission electron microscopy observation revealed disruptions of cell envelopes accompanied by leakage of intracellular contents. Similarly, the bactericidal activity of the holin and endolysin against V. alginolyticus was also examined whatever the host is sensitive or resistant to phage HH109. Together, our study contributes to a better understanding of the mechanism of phage HH109 destroying the bacterial cell wall to lyse their host and may offer alternative applications potentially for vibriosis treatment.


Assuntos
Bacteriófagos , Animais , Bacteriófagos/genética , Endopeptidases/genética , Escherichia coli , Vibrio alginolyticus
9.
Nutrients ; 13(8)2021 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-34444819

RESUMO

This study investigated peptide fractions from fish skin collagen for antibacterial activity against Escherichia coli and Salmonella strains. The collagen was hydrolyzed with six commercial proteases, including trypsin, Alcalase, Neutrase, Flavourzyme, pepsin and papain. Hydrolyzed samples obtained with trypsin and Alcalase had the largest number of small peptides (molecular weight <10 kDa), while the hydrolysate produced with papain showed the lowest degree of hydrolysis and highest number of large peptides. Four hydrolysates were found to inhibit the growth of the Gram-negative bacteria, with papain hydrolysate showing the best activity against E. coli, and Neutrase and papain hydrolysates showing the best activity against S. abony; hydrolysates produced with trypsin and pepsin did not show detectable antibacterial activity. After acetone fractionation of the latter hydrolysates, the peptide fractions demonstrated enhanced dose-dependent inhibition of the growth (colony-forming units) of four Salmonella strains, including S. abony (NCTC 6017), S. typhimurium (ATCC 13311), S. typhimurium (ATCC 14028) and S. chol (ATCC 10708). Shotgun peptidomics analysis of the acetone fractions of Neutrase and papain hydrolysates resulted in the identification of 71 and 103 peptides, respectively, with chain lengths of 6-22 and 6-24, respectively. This work provided an array of peptide sequences from fish skin collagen for pharmacophore identification, structure-activity relationship studies, and further investigation as food-based antibacterial agents against pathogenic microorganisms.


Assuntos
Antibacterianos/farmacologia , Colágeno/química , Peixes , Peptídeos/farmacologia , Salmonella/efeitos dos fármacos , Pele/química , Animais , Endopeptidases , Escherichia coli/efeitos dos fármacos , Hidrólise , Metaloendopeptidases , Peso Molecular , Papaína , Pepsina A , Peptídeo Hidrolases , Peptidomiméticos , Hidrolisados de Proteína/farmacologia , Subtilisinas , Tripsina
10.
Theranostics ; 11(16): 7755-7766, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34335962

RESUMO

Background: Myocardial infarction (MI) evokes an organized remodeling process characterized by the activation and transdifferentiation of quiescent cardiac fibroblasts to generate a stable collagen rich scar. Early fibroblast activation may be amenable to targeted therapy, but is challenging to identify in vivo. We aimed to non-invasively image active fibrosis by targeting the fibroblast activation protein (FAP) expressed by activated (myo)fibroblasts, using a novel positron emission tomography (PET) radioligand [68Ga]MHLL1 after acute MI. Methods: One-step chemical synthesis and manual as well as module-based radiolabeling yielded [68Ga]MHLL1. Binding characteristics were evaluated in murine and human FAP-transfected cells, and stability tested in human serum. Biodistribution in healthy animals was interrogated by dynamic PET imaging, and metabolites were measured in blood and urine. The temporal pattern of FAP expression was determined by serial PET imaging at 7 d and 21 d after coronary artery ligation in mice as percent injected dose per gram (%ID/g). PET measurements were validated by ex vivo autoradiography and immunostaining for FAP and inflammatory macrophages. Results: [68Ga]MHLL1 displayed specific uptake in murine and human FAP-positive cells (p = 0.0208). In healthy mice the tracer exhibited favorable imaging characteristics, with low blood pool retention and dominantly renal clearance. At 7 d after coronary artery ligation, [68Ga]MHLL1 uptake was elevated in the infarct relative to the non-infarcted remote myocardium (1.3 ± 0.3 vs. 1.0 ± 0.2 %ID/g, p < 0.001) which persisted to 21 d after MI (1.3 ± 0.4 vs. 1.1 ± 0.4 %ID/g, p = 0.013). Excess unlabeled compound blocked tracer accumulation in both infarct and non-infarct remote myocardium regions (p < 0.001). Autoradiography and histology confirmed the regional uptake of [68Ga]MHLL1 in the infarct and especially border zone regions, as identified by Masson trichrome collagen staining. Immunostaining further delineated persistent FAP expression at 7 d and 21 d post-MI in the border zone, consistent with tracer distribution in vivo. Conclusion: The simplified synthesis of [68Ga]MHLL1 bears promise for non-invasive characterization of fibroblast activation protein early in remodeling after MI.


Assuntos
Endopeptidases/metabolismo , Radioisótopos de Gálio/farmacologia , Proteínas de Membrana/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Animais , Autorradiografia/métodos , Linhagem Celular Tumoral , Endopeptidases/fisiologia , Fibroblastos/metabolismo , Fibrose/diagnóstico por imagem , Radioisótopos de Gálio/metabolismo , Humanos , Masculino , Proteínas de Membrana/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Imagem Molecular/métodos , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/fisiopatologia , Miocárdio/patologia , Distribuição Tecidual/fisiologia , Tomografia Computadorizada por Raios X/métodos
11.
Int J Mol Sci ; 22(15)2021 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-34361120

RESUMO

A major limiting factor for systemically delivered gene therapies is the lack of novel tissue specific AAV (Adeno-associated virus) derived vectors. Bispecific antibodies can be used to redirect AAVs to specific target receptors. Here, we demonstrate that the insertion of a short linear epitope "2E3" derived from human proprotein-convertase subtilisin/kexin type 9 (PCSK9) into different surface loops of the VP capsid proteins can be used for AAV de-targeting from its natural receptor(s), combined with a bispecific antibody-mediated retargeting. We chose to target a set of distinct disease relevant membrane proteins-fibroblast activation protein (FAP), which is upregulated on activated fibroblasts within the tumor stroma and in fibrotic tissues, as well as programmed death-ligand 1 (PD-L1), which is strongly upregulated in many cancers. Upon incubation with a bispecific antibody recognizing the 2E3 epitope and FAP or PD-L1, the bispecific antibody/rAAV complex was able to selectively transduce receptor positive cells. In summary, we developed a novel, rationally designed vector retargeting platform that can target AAVs to a new set of cellular receptors in a modular fashion. This versatile platform may serve as a valuable tool to investigate the role of disease relevant cell types and basis for novel gene therapy approaches.


Assuntos
Anticorpos Biespecíficos/imunologia , Proteínas do Capsídeo/imunologia , Capsídeo/imunologia , Dependovirus/genética , Endopeptidases/imunologia , Epitopos/imunologia , Vetores Genéticos/administração & dosagem , Proteínas de Membrana/imunologia , Capsídeo/metabolismo , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Endopeptidases/genética , Endopeptidases/metabolismo , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos/genética , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/imunologia , Pró-Proteína Convertase 9/metabolismo , Transdução Genética
12.
Int J Mol Sci ; 22(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34360587

RESUMO

In the present study, we analyzed the activity of several aminopeptidases (angiotensinases) involved in the metabolism of various angiotensin peptides, in pituitary and adrenal glands of untreated Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) or treated with the antihypertensive drugs captopril and propranolol or with the L-Arginine hypertensive analogue L-NG-Nitroarginine Methyl Ester (L-NAME). Intra- and inter-gland correlations between angiotensinase activities were also calculated. Membrane-bound alanyl-, cystinyl-, and glutamyl-aminopeptidase activities were determined fluorometrically using aminoacyl-ß-naphthylamide as substrates. Depending on the type of angiotensinase analyzed, the results reflect a complex picture showing substantial differences between glands, strains, and treatments. Alanyl-aminopeptidase responsible for the metabolism of Ang III to Ang IV appears to be the most active angiotensinase in both pituitary and adrenals of WKY and particularly in SHR. Independently of treatment, most positive correlations are observed in the pituitary gland of WKY whereas such positive correlations are predominant in adrenals of SHR. Negative inter-gland correlations were observed in control SHR and L-NAME treated WKY. Positive inter-gland correlations were observed in captopril-treated SHR and propranolol-treated WKY. These results may reflect additional mechanisms for increasing or decreasing systolic blood pressure in WKY or SHR.


Assuntos
Glândulas Suprarrenais/metabolismo , Anti-Hipertensivos/farmacologia , Endopeptidases/metabolismo , Hipertensão/metabolismo , Hipotensão/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Hipófise/metabolismo , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Captopril/farmacologia , Endopeptidases/genética , Inibidores Enzimáticos/farmacologia , Regulação Enzimológica da Expressão Gênica , Hipertensão/tratamento farmacológico , Hipertensão/patologia , Hipotensão/tratamento farmacológico , Hipotensão/patologia , Masculino , Hipófise/efeitos dos fármacos , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
13.
Enzyme Microb Technol ; 149: 109846, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34311883

RESUMO

Antibiotic resistance has become a major risk to community health over last few years because of antibiotics overuse around the globe and lack of new antibiotics development. Phages and their lytic enzymes are considered as an effective alternative of antibiotics to control drug resistant bacterial pathogens. Endolysins prove to be a promising class of antibacterials due to their specificity and less chances of resistance development in bacterial pathogens. Though large number of endolysins has been reported against gram positive bacteria, very few reported against gram negative bacteria due to the presence of outer membrane, which acts as physical barrier against endolysin attack to peptidoglycan. In the current study, we have expressed endolysin (RL_Lys) and holin fused at the N terminus of endolysin (RL_Hlys) from RL phage infecting multi drug resistant (MDR) Pseudomonas aeruginosa. Both endolysin variants were found active against wide range of MDR strains P. aeruginosa, Klebsella pneumonia, Salmonella Sp. and Methicillin Resistant Staphylococcus aureus (MRSA). Broth reduction assay showed that RL_Hlys is more active than RL_Lys due to presence of holin, which assist the endolysin access towards cell wall. The protein ligand docking and molecular dynamic simulation results showed that C- terminus region of endolysin play vital role in cell wall binding and even in the absence of holin, hydrolyze a broad range of gram negative bacterial pathogens. The significant activity of RL-Lys and RL_Hlys against a broad range of MDR gram negative and positive bacterial pathogens makes them good candidates for antibiotic alternatives.


Assuntos
Antibacterianos , Bacteriófagos , Endopeptidases , Antibacterianos/farmacologia , Bacteriófagos/genética , Clonagem Molecular , Farmacorresistência Bacteriana Múltipla , Endopeptidases/genética , Endopeptidases/farmacologia , Klebsiella , Staphylococcus aureus Resistente à Meticilina , Pseudomonas aeruginosa , Salmonella
14.
Bioresour Technol ; 340: 125627, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34330004

RESUMO

Transglutaminase forms isopeptide bonds in proteins which are helpful in various industrial applications. However, low productivity and high cost are the major bottlenecks for industrial Transglutaminase production. The present study describes the regulatory mechanism of microbial Transglutaminase (MTGase) biosynthesis from Streptomyces mobaraensis and the effect of key regulators to maximize production. The transcriptional responses under the effect of various key modulators of MTGasebiosynthesis were evaluated. Productivity of MTGase with novel biosynthesis approach by regulators augmentation was correlated by transcriptional profiling. The optimization by key modulators by combinational supplementation led to 2-fold rise in activity. The functional attributes, the copy number of MTGase gene and relative changes were assessed by Real-Time quantitative PCR. Protease, MgCl2, CTAB induced upregulation, whereas PMSF, NaF and bleomycin sulphate showed inhibitory action on MTGase production and activity. The optimization by combinational supplementation of key modulators led to 4.27-fold increase (6.11 IU/mL) in production.


Assuntos
Streptomyces , Transglutaminases , Endopeptidases , Proteínas , Streptomyces/genética , Transglutaminases/genética
15.
Antimicrob Agents Chemother ; 65(9): e0272320, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34228536

RESUMO

Exebacase (CF-301) is a novel antistaphylococcal lysin (cell wall hydrolase) in phase 3 of clinical development for the treatment of Staphylococcus aureus bacteremia, including right-sided endocarditis, used in addition to standard-of-care antibiotics. In the current study, the potential for exebacase to treat S. aureus pneumonia was explored in vitro using bovine pulmonary surfactant (Survanta) and in vivo using a lethal murine pneumonia model. Exebacase was active against a set of methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) strains, with an MIC90 of 2 µg/ml (n = 18 strains), in the presence of a surfactant concentration (7.5%) inhibitory to the antistaphylococcal antibiotic daptomycin, which is inactive in pulmonary environments due to specific inhibition by surfactant. In a rigorous test of the ability of exebacase to synergize with antistaphylococcal antibiotics, exebacase synergized with daptomycin in the presence of surfactant in vitro, resulting in daptomycin MIC reductions of up to 64-fold against 9 MRSA and 9 MSSA strains. Exebacase was also observed to facilitate the binding of daptomycin to S. aureus and the elimination of biofilm-like structures formed in the presence of surfactant. Exebacase (5 mg/kg of body weight 1 time every 24 h [q24h], administered intravenously for 3 days) was efficacious in a murine model of staphylococcal pneumonia, resulting in 50% survival, compared to 0% survival with the vehicle control; exebacase in addition to daptomycin (50 mg/kg q24h for 3 days) resulted in 70% survival, compared to 0% survival in the daptomycin-alone control group. Overall, exebacase is active in pulmonary environments and may be appropriate for development as a treatment for staphylococcal pneumonia.


Assuntos
Daptomicina , Staphylococcus aureus Resistente à Meticilina , Pneumonia Estafilocócica , Surfactantes Pulmonares , Infecções Estafilocócicas , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Daptomicina/farmacologia , Modelos Animais de Doenças , Endopeptidases , Pulmão , Camundongos , Testes de Sensibilidade Microbiana , Pneumonia Estafilocócica/tratamento farmacológico , Infecções Estafilocócicas/tratamento farmacológico , Staphylococcus aureus
16.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281200

RESUMO

The best-characterized members of the M23 family are glycyl-glycine hydrolases, such as lysostaphin (Lss) from Staphylococcus simulans or LytM from Staphylococcus aureus. Recently, enzymes with broad specificities were reported, such as EnpACD from Enterococcus faecalis, that cleaves D,L peptide bond between the stem peptide and a cross-bridge. Previously, the activity of EnpACD was demonstrated only on isolated peptidoglycan fragments. Herein we report conditions in which EnpACD lyses bacterial cells live with very high efficiency demonstrating great bacteriolytic potential, though limited to a low ionic strength environment. We have solved the structure of the EnpACD H109A inactive variant and analyzed it in the context of related peptidoglycan hydrolases structures to reveal the bases for the specificity determination. All M23 structures share a very conserved ß-sheet core which constitutes the rigid bottom of the substrate-binding groove and active site, while variable loops create the walls of the deep and narrow binding cleft. A detailed analysis of the binding groove architecture, specificity of M23 enzymes and D,L peptidases demonstrates that the substrate groove, which is particularly deep and narrow, is accessible preferably for peptides composed of amino acids with short side chains or subsequent L and D-isomers. As a result, the bottom of the groove is involved in interactions with the main chain of the substrate while the side chains are protruding in one plane towards the groove opening. We concluded that the selectivity of the substrates is based on their conformations allowed only for polyglycine chains and alternating chirality of the amino acids.


Assuntos
Endopeptidases/metabolismo , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Peptídeo Hidrolases/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/metabolismo , Domínio Catalítico , Enterococcus faecalis/genética , Enterococcus faecalis/metabolismo , Peptidoglicano/metabolismo , Prófagos/genética , Prófagos/metabolismo , Ligação Proteica , Staphylococcus/metabolismo , Staphylococcus aureus/metabolismo , Especificidade por Substrato
17.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298967

RESUMO

Pathological fibrosis of the liver is a landmark feature in chronic liver diseases, including nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Diagnosis and assessment of progress or treatment efficacy today requires biopsy of the liver, which is a challenge in, e.g., longitudinal interventional studies. Molecular imaging techniques such as positron emission tomography (PET) have the potential to enable minimally invasive assessment of liver fibrosis. This review will summarize and discuss the current status of the development of innovative imaging markers for processes relevant for fibrogenesis in liver, e.g., certain immune cells, activated fibroblasts, and collagen depositions.


Assuntos
Imagem Molecular/tendências , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Alarminas/metabolismo , Animais , Aquaporinas/análise , Colágeno/análise , Meios de Contraste , Citocinas/metabolismo , Técnicas de Imagem por Elasticidade/métodos , Endopeptidases/análise , Ácidos Graxos/metabolismo , Fibroblastos/química , Fibroblastos/ultraestrutura , Radioisótopos de Flúor , Radioisótopos de Gálio , Células Estreladas do Fígado/química , Células Estreladas do Fígado/ultraestrutura , Hepatócitos/metabolismo , Humanos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia , Cirrose Hepática/metabolismo , Proteínas de Membrana/análise , Camundongos , Imagem Molecular/métodos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Ratos , Receptores CCR2/análise , Triglicerídeos/metabolismo
18.
Molecules ; 26(12)2021 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-34201111

RESUMO

Recently, the first squaramide-(SA) containing FAP inhibitor-derived radiotracers were introduced. DATA5m.SA.FAPi and DOTA.SA.FAPi with their non-radioactive complexes showed high affinity and selectivity for FAP. After a successful preclinical study with [68Ga]Ga-DOTA.SA.FAPi, the first patient studies were realized for both compounds. Here, we present a new squaramide-containing compound targeting FAP, based on the AAZTA5 chelator 1,4-bis-(carboxylmethyl)-6-[bis-(carboxymethyl)-amino-6-pentanoic-acid]-perhydro-1,4-diazepine. For this molecule (AAZTA5.SA.FAPi), complexation with radionuclides such as gallium-68, scandium-44, and lutetium-177 was investigated, and the in vitro properties of the complexes were characterized and compared with those of DOTA.SA.FAPi. AAZTA5.SA.FAPi and its derivatives labelled with non-radioactive isotopes demonstrated similar excellent inhibitory potencies compared to the previously published SA.FAPi ligands, i.e., sub-nanomolar IC50 values for FAP and high selectivity indices over the serine proteases PREP and DPPs. Labeling with all three radiometals was easier and faster with AAZTA5.SA.FAPi compared to the corresponding DOTA analogue at ambient temperature. Especially, scandium-44 labeling with the AAZTA derivative resulted in higher specific activities. Both DOTA.SA.FAPi and AAZTA5.SA.FAPi showed sufficiently high stability in different media. Therefore, these FAP inhibitor agents could be promising for theranostic approaches targeting FAP.


Assuntos
Acetatos/farmacologia , Azepinas/farmacologia , Fibroblastos/efeitos dos fármacos , Compostos Heterocíclicos com 1 Anel/farmacologia , Proteínas de Membrana/antagonistas & inibidores , Quinina/análogos & derivados , Endopeptidases , Fibroblastos/metabolismo , Radioisótopos de Gálio/farmacologia , Humanos , Ligantes , Lutécio/farmacologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Quinina/farmacologia , Radioisótopos/farmacologia , Compostos Radiofarmacêuticos/farmacologia , Escândio/farmacologia , Serina Endopeptidases/metabolismo
19.
Appl Microbiol Biotechnol ; 105(13): 5461-5470, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34241646

RESUMO

Foodborne pathogens have caused many public health incidents and heavy economic burden. Endolysins have been proven to have efficient bactericidal activity against pathogens with low incidence of resistance. In this study, the recombinant endolysin LysSP1 encoded by Salmonella Typhimurium lytic bacteriophage SLMP1 was obtained by prokaryotic expression, and its characteristics were analyzed. Ethylenediaminetetraacetic acid (EDTA) can be used as the outer membrane permeabilizer to increase the bactericidal activity of LysSP1. Under the synergism of 5 mmol/L EDTA, LysSP1 exhibited a strong bactericidal activity against Salmonella Typhimurium ATCC14028. LysSP1 was stable at 4°C for 7 days and at -20°C for 180 days. LysSP1 remained the optimal activity at 40°C and was efficiently active at alkaline condition (pH 8.0-10.0). Divalent metal ions could not enhance the bactericidal activity of LysSP1 and even caused the significant reduction of bactericidal activity. LysSP1 not only could lyse Salmonella, but also could lyse other Gram-negative strains and Gram-positive strains. These results indicated that LysSP1 is a broad-spectrum endolysin and has potential as an antimicrobial agent against Salmonella and other foodborne pathogens. KEY POINTS: • Recombinant endolysin LysSP1 can be prepared by prokaryotic expression. • LysSP1 has stable nature and strong bactericidal activity on Salmonella Typhimurium with EDTA. • LysSP1 has a broad range of hosts including Gram-negative bacteria and Gram-positive bacteria.


Assuntos
Fagos de Salmonella , Antibacterianos , Endopeptidases/genética , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Fagos de Salmonella/genética
20.
Molecules ; 26(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201554

RESUMO

The Angiotensin-I-converting enzyme (ACE) is a peptidase with a significant role in the regulation of blood pressure. Within this work, a systematic review on the enzymatic preparation of Angiotensin-I-Converting Enzyme inhibitory (ACEi) peptides is presented. The systematic review is conducted by following PRISMA guidelines. Soybeans and velvet beans are known to have high protein contents that make them suitable as sources of parent proteins for the production of ACEi peptides. Endopeptidase is commonly used in the preparation of soybean-based ACEi peptides, whereas for velvet bean, a combination of both endo- and exopeptidase is frequently used. Soybean glycinin is the preferred substrate for the preparation of ACEi peptides. It contains proline as one of its major amino acids, which exhibits a potent significance in inhibiting ACE. The best enzymatic treatments for producing ACEi peptides from soybean are as follows: proteolytic activity by Protease P (Amano-P from Aspergillus sp.), a temperature of 37 °C, a reaction time of 18 h, pH 8.2, and an E/S ratio of 2%. On the other hand, the best enzymatic conditions for producing peptide hydrolysates with high ACEi activity are through sequential hydrolytic activity by the combination of pepsin-pancreatic, an E/S ratio for each enzyme is 10%, the temperature and reaction time for each proteolysis are 37 °C and 0.74 h, respectively, pH for pepsin is 2.0, whereas for pancreatin it is 7.0. As an underutilized pulse, the studies on the enzymatic hydrolysis of velvet bean proteins in producing ACEi peptides are limited. Conclusively, the activity of soybean-based ACEi peptides is found to depend on their molecular sizes, the amino acid residues, and positions. Hydrophobic amino acids with nonpolar side chains, positively charged, branched, and cyclic or aromatic residues are generally preferred for ACEi peptides.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Mucuna/metabolismo , Soja/metabolismo , Aminoácidos/química , Inibidores da Enzima Conversora de Angiotensina/química , Aspergillus/enzimologia , Endopeptidases/química , Exopeptidases/química , Globulinas/química , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Pancreatina/química , Peptídeo Hidrolases/química , Peptídeos/química , Prolina/química , Proteínas de Soja/química , Temperatura
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