scholarly journals Computational design of anti-CRISPR proteins with improved inhibition potency and expanded specificity

2019 ◽  
Author(s):  
Jan Mathony ◽  
Zander Harteveld ◽  
Carolin Schmelas ◽  
Julius Upmeier zu Belzen ◽  
Sabine Aschenbrenner ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Broad Spectrum ◽  
Potent Inhibitor ◽  
Computational Design ◽  
Type Ii ◽  
Innovative Strategy ◽  
Naturally Occurring ◽  
Mining Sequence ◽  
Inhibition Potency

AbstractAnti-CRISPR (Acr) proteins are bacteriophage-derived antagonists of CRISPR-Cas systems. To date, Acrs were obtained either by mining sequence databanks or experimentally screening phage collections, both of which yield a limited repertoire of naturally occurring variants. Here, we applied structure-based engineering on AcrIIC1, a broad-spectrum inhibitor of type II-C CRISPR systems, to improve its efficacy and expand its specificity. We first show that fusing exogenous protein domains into AcrIIC1 dramatically enhances inhibition of the natural Neisseria meningitidis Cas9 target. Then, using structure-guided design, we converted AcrIIC1 into AcrX, a potent inhibitor of the type II-A CRISPR-Cas9 from Staphylococcus aureus widely applied for in vivo genome editing. Our work introduces designer Acrs as important biotechnological tools and provides an innovative strategy to safeguard the CRISPR technology.

scholarly journals In Vivo Efficacy of Ceftaroline (PPI-0903), a New Broad-Spectrum Cephalosporin, Compared with Linezolid and Vancomycin against Methicillin-Resistant and Vancomycin-Intermediate Staphylococcus aureus in a Rabbit Endocarditis Model

2007 ◽  
Vol 51 (9) ◽  
pp. 3397-3400 ◽  
Author(s):  
Cédric Jacqueline ◽  
Jocelyne Caillon ◽  
Virginie Le Mabecque ◽  
Anne-Françoise Miègeville ◽  
Antoine Hamel ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Broad Spectrum ◽  
Day Treatment ◽  
Effective Drug ◽  
In Vivo Efficacy ◽  
Methicillin Resistant

ABSTRACT Using the rabbit endocarditis model, we compared the activity of a new broad-spectrum cephalosporin, ceftaroline, with those of linezolid and vancomycin against methicillin-resistant Staphylococcus aureus. After a 4-day treatment, ceftaroline exhibited superior bactericidal in vivo activity against resistant S. aureus strains and appeared to be the most effective drug against a heterogeneous glycopeptide-intermediate S. aureus strain.

scholarly journals Oral Administration of the Broad-Spectrum Antibiofilm Compound Toremifene Inhibits Candida albicans and Staphylococcus aureus Biofilm FormationIn Vivo

2014 ◽  
Vol 58 (12) ◽  
pp. 7606-7610 ◽  
Author(s):  
Kaat De Cremer ◽  
Nicolas Delattin ◽  
Katrijn De Brucker ◽  
Annelies Peeters ◽  
Soña Kucharíková ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Candida Albicans ◽  
Broad Spectrum ◽  
Staphylococcus Epidermidis ◽  
Biofilm Formation ◽  
Candida Krusei ◽  
Content Type ◽  
And Staphylococcus Aureus

ABSTRACTWe here report on thein vitroactivity of toremifene to inhibit biofilm formation of different fungal and bacterial pathogens, includingCandida albicans,Candida glabrata,Candida dubliniensis,Candida krusei,Pseudomonas aeruginosa,Staphylococcus aureus, andStaphylococcus epidermidis. We validated thein vivoefficacy of orally administered toremifene againstC. albicans and S. aureusbiofilm formation in a rat subcutaneous catheter model. Combined, our results demonstrate the potential of toremifene as a broad-spectrum oral antibiofilm compound.

Fibrinolysis Versus Fibrinogenolysis: The Specificity of Human Vascular Activator (VA) as Compared to Urokinase (UK) and Streptokinase (SK)

1975 ◽  
Author(s):  
B. Lipinski ◽  
V. Gurewich ◽  
E. Hyde
Keyword(s):  
Human Blood ◽  
Potent Inhibitor ◽  
Solid Phase ◽  
Proteolytic Enzymes ◽  
Plasminogen Activators ◽  
Venous Occlusion ◽  
Normal Serum ◽  
Naturally Occurring

Activation of fibrinolysis by venous occlusion or exercise was shown previously not to cause degradation of plasma fibrinogen either in vivo or in vitro. The proteolytic effect of activated fibrinolysis was evident only when substrate was in a solid phase (fibrin or precipitated fibrinogen). In this study, clotted and unclotted plasma was incubated at 37° C for 18 hours with 3 activators. SK and UK induced degradation of both fibrin and fibrinogen, whereas VA was active exclusively on the fibrin substrate. Moreover, VA did not alter the mobility and concentration of 2 fibrinogen fractions found on plasma electrophoresis in 3.5% SDS-polyacrylamide gel. However, when VA was incubated with isolated fibrinogen (plasminogen rich) degradation took place. The addition to this purified system of normal serum or plasma diluted up to 100-fold, inhibited fibrinogenolysis but not fibrinolysis. It is concluded from these experiments that human blood contains a specific and highly potent inhibitor which forms a complex with VA. Dissociation of this complex requires a solid phase thus allowing plasminogen to be activated. This inhibitor appears to be highly specific for VA. It is postulated that direct fibrinogenolysis in man is not induced by naturally occurring plasminogen activators. The catabolism of fibrinogen may involve other proteolytic enzymes, or alternatively an intermediate solid phase.

790: BMP-7 is a Potent Inhibitor of Prostate Cancer Bone Metastasis in Vivo

2006 ◽  
Vol 175 (4S) ◽  
pp. 255-256
Author(s):  
Cyrill A. Rentsch ◽  
Jeroen Buijs ◽  
Geertje Van der Horst ◽  
Petra Van Overveld ◽  
Antoinette Wetterwald ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Bone Metastasis ◽  
Potent Inhibitor

In vivo glucose metabolism in obese and type II diabetic subjects with or without hypertension

Diabetes ◽  
1993 ◽  
Vol 42 (5) ◽  
pp. 764-772 ◽  
Author(s):  
E. Bonora ◽  
R. C. Bonadonna ◽  
S. Del Prato ◽  
G. Gulli ◽  
A. Solini ◽  
...  
Keyword(s):  
Glucose Metabolism ◽  
Type Ii

The Study of Bacillus Subtils Antimicrobial Activity on Some of the Pathological Isolates

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Hussein A Kadhum ◽  
Thualfakar H Hasan2
Keyword(s):  
Staphylococcus Aureus ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Activity ◽  
Bacillus Subtilis ◽  
Bacterial Growth ◽  
Broad Spectrum ◽  
Inhibitory Activity ◽  
Bacterial Pathogens ◽  
Inhibitory Ability ◽  
Selection Of

The study involved the selection of two isolates from Bacillus subtilis to investigate their inhibitory activity against some bacterial pathogens. B sub-bacteria were found to have a broad spectrum against test bacteria such as Staphylococcus aureus and Pseudomonas aeruginosa. They were about 23-30 mm and less against Klebsiella sp. The sensitivity of some antibodies was tested on the test samples. The results showed that the inhibitory ability of bacterial growth in the test samples using B. subtilis extract was more effective than the antibiotics used.

Garlic Extract (Allium sativum L.) Effectively Inhibits Staphylococcus aureus and Escherichia coli by Invitro Test

2020 ◽  
Vol 2 (2) ◽  
pp. 61-68
Author(s):  
Agnina Listya Anggraini ◽  
Ratih Dewi Dwiyanti ◽  
Anny Thuraidah
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Bacterial Infections ◽  
Allium Sativum ◽  
Antibacterial Properties ◽  
Herbal Medicines ◽  
Garlic Extract ◽  
Dilution Method ◽  
Initial Stage

Infection is a disease caused by the presence of pathogenic microbes, including Staphylococcus aureus and Escherichia coli. Garlic (Allium sativum L.) has chemical contents such as allicin, alkaloids, flavonoids, saponins, tannins, and steroids, which can function as an antibacterial against Staphylococcus aureus and Escherichia coli. This study aims to determine the antibacterial properties of garlic extract powder against Staphylococcus aureus and Escherichia coli. This research is the initial stage of the development of herbal medicines to treat Staphylococcus aureus and Escherichia coli infections. The antibacterial activity test was carried out by the liquid dilution method. The concentrations used were 30 mg/mL, 40 mg/mL, 50 mg/mL, 60 mg/mL and 70 mg/mL. The results showed that the Minimum Inhibitory Concentration (MIC) against Staphylococcus aureus and Escherichia coli was 40 mg/mL and 50 mg / mL. Minimum Bactericidal Concentration (MBC) results for Staphylococcus aureus and Escherichia coli are 50 mg/mL and 70 mg/mL. Based on the Simple Linear Regression test, the R2 value of Staphylococcus aureus and Escherichia coli is 0.545 and 0.785, so it can be concluded that there is an effect of garlic extract powder on the growth of Staphylococcus aureus and Escherichia coli by 54.5% and 78.5%. Garlic (Allium sativum L.) extract powder has potential as herbal medicine against bacterial infections but requires further research to determine its effect in vivo.

Design, Synthesis, and Pharmacokinetic Evaluation of O-Carbamoyl Tizoxanide Prodrugs

2020 ◽  
Vol 16 ◽  
Author(s):  
Xi He ◽  
Wenjun Hu ◽  
Fanhua Meng ◽  
Xingzhou Li
Keyword(s):  
Plasma Concentration ◽  
Broad Spectrum ◽  
Plasma Concentrations ◽  
Antiviral Drug ◽  
Systemic Exposure ◽  
Pharmacokinetic Profile ◽  
Hydroxyl Group ◽  
First Pass

Background: The broad-spectrum antiparasitic drug nitazoxanide (N) has been repositioned as a broad-spectrum antiviral drug. Nitazoxanide’s in vivo antiviral activities are mainly attributed to its metabolitetizoxanide, the deacetylation product of nitazoxanide. In reference to the pharmacokinetic profile of nitazoxanide, we proposed the hypotheses that the low plasma concentrations and the low system exposure of tizoxanide after dosing with nitazoxanide result from significant first pass effects in the liver. It was thought that this may be due to the unstable acyloxy bond of nitazoxanide. Objective: Tizoxanide prodrugs, with the more stable formamyl substituent attached to the hydroxyl group rather than the acetyl group of nitazoxanide, were designed with the thought that they might be more stable in plasma. It was anticipated that these prodrugs might be less affected by the first pass effect, which would improve plasma concentrations and system exposure of tizoxanide. Method: These O-carbamoyl tizoxanide prodrugs were synthesized and evaluated in a mouse model for pharmacokinetic (PK) properties and in an in vitro model for plasma stabilities. Results: The results indicated that the plasma concentration and the systemic exposure of tizoxanide (T) after oral administration of O-carbamoyl tizoxanide prodrugs were much greater than that produced by equimolar dosage of nitazoxanide. It was also found that the plasma concentration and the systemic exposure of tizoxanide glucuronide (TG) were much lower than that produced by nitazoxanide. Conclusion: Further analysis showed that the suitable plasma stability of O-carbamoyl tizoxanide prodrugs is the key factor in maximizing the plasma concentration and the systemic exposure of the active ingredient tizoxanide.

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