Determination of Half-Maximal Inhibitory Concentration of an Enzyme Inhibitor

Georgakis, Nikolaos; Ioannou, Elisavet; Varotsou, Christina; Premetis, Georgios; Chronopoulou, Evangelia; Labrou, Nikolaos E.

doi:10.1007/978-1-0716-0163-1_3

Cited by 8 publications

(6 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4 B) were markedly inhibited by 0.1 µM GBS. The IC50 value is widely used as the informative measure of an enzyme inhibitor’s efficacy 28 . The results showed that Nf-LacZ had an IC50 value of 0.59 µM (Fig.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Characterization of two β-galactosidases LacZ and WspA1 from Nostoc flagelliforme with focus on the latter’s central active region

Gao

Liu

Cui

et al. 2021

Sci Rep

View full text Add to dashboard Cite

The identification and characterization of new β-galactosidases will provide diverse candidate enzymes for use in food processing industry. In this study, two β-galactosidases, Nf-LacZ and WspA1, from the terrestrial cyanobacterium Nostoc flagelliforme were heterologously expressed in Escherichia coli, followed by purification and biochemical characterization. Nf-LacZ was characterized to have an optimum activity at 40 °C and pH 6.5, different from that (45 °C and pH 8.0) of WspA1. Two enzymes had a similar Michaelis constant (Km = 0.5 mmol/liter) against the substrate o-nitrophenyl-β-D-galactopyranoside. Their activities could be inhibited by galactostatin bisulfite, with IC50 values of 0.59 µM for Nf-LacZ and 1.18 µM for WspA1, respectively. Gel filtration analysis suggested that the active form of WspA1 was a dimer, while Nf-LacZ was functional as a larger multimer. WspA1 was further characterized by the truncation test, and its minimum central region was found to be from residues 188 to 301, having both the glycosyl hydrolytic and transgalactosylation activities. Finally, transgenic analysis with the GFP reporter protein found that the N-terminus of WspA1 (35 aa) might play a special role in the export of WspA1 from cells. In summary, this study characterized two cyanobacterial β-galactosidases for potential applications in food industry.

show abstract

Section: Resultsmentioning

confidence: 99%

“…The half-maximal inhibitory concentration (IC50) represents the concentration of a substance (e.g. a drug) that is required for 50% inhibition in a specific biological or biochemical function 28 . The IC50 values of the galactosidases in response to GBS inhibition were assayed as previously described 29 with slight modification.…”

Section: Methodsmentioning

confidence: 99%

Characterization of two β-galactosidases LacZ and WspA1 from Nostoc flagelliforme with focus on the latter’s central active region

Gao

Liu

Cui

et al. 2021

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The half-maximal inhibitory concentrations (IC 50 ) are a measure of the effectiveness of a compound in inhibiting biological function [ 22 ].…”

Section: Methodsmentioning

confidence: 99%

Novel Drug Design for Treatment of COVID-19: A Systematic Review of Preclinical Studies

Mousavi

Zare

Mirzaei

et al. 2022

Canadian Journal of Infectious Diseases and Medical Microbiolog

View full text Add to dashboard Cite

Background. Since the beginning of the novel coronavirus (SARS-CoV-2) disease outbreak, there has been an increasing interest in discovering potential therapeutic agents for this disease. In this regard, we conducted a systematic review through an overview of drug development (in silico, in vitro, and in vivo) for treating COVID-19. Methods. A systematic search was carried out in major databases including PubMed, Web of Science, Scopus, EMBASE, and Google Scholar from December 2019 to March 2021. A combination of the following terms was used: coronavirus, COVID-19, SARS-CoV-2, drug design, drug development, In silico, In vitro, and In vivo. A narrative synthesis was performed as a qualitative method for the data synthesis of each outcome measure. Results. A total of 2168 articles were identified through searching databases. Finally, 315 studies (266 in silico, 34 in vitro, and 15 in vivo) were included. In studies with in silico approach, 98 article study repurposed drug and 91 studies evaluated herbal medicine on COVID-19. Among 260 drugs repurposed by the computational method, the best results were observed with saquinavir (n = 9), ritonavir (n = 8), and lopinavir (n = 6). Main protease (n = 154) following spike glycoprotein (n = 62) and other nonstructural protein of virus (n = 45) was among the most studied targets. Doxycycline, chlorpromazine, azithromycin, heparin, bepridil, and glycyrrhizic acid showed both in silico and in vitro inhibitory effects against SARS-CoV-2. Conclusion. The preclinical studies of novel drug design for COVID-19 focused on main protease and spike glycoprotein as targets for antiviral development. From evaluated structures, saquinavir, ritonavir, eucalyptus, Tinospora cordifolia, aloe, green tea, curcumin, pyrazole, and triazole derivatives in in silico studies and doxycycline, chlorpromazine, and heparin from in vitro and human monoclonal antibodies from in vivo studies showed promised results regarding efficacy. It seems that due to the nature of COVID-19 disease, finding some drugs with multitarget antiviral actions and anti-inflammatory potential is valuable and some herbal medicines have this potential.

show abstract

“…The results showed that between these herbicides, butachlor displayed substantial potency towards all the tested enzymes. Dose-response measurements allowed the determination of IC50 of butachlor towards all the enzymes [51]. The values estimated among the wild-type enzymes did not show significant differences in inhibition potency among weed (LrGSTF and AmGSTF) and crop (TdGSTF and HvGSTF) enzymes.…”

Section: Determination Of Butachlor's Half-maximal Inhibitory Concent...mentioning

confidence: 99%

Directed Evolution of Phi Class Glutathione Transferases Involved in Multiple-Herbicide Resistance of Grass Weeds and Crops

Ioannou

Papageorgiou

Labrou

2022

IJMS

Self Cite

View full text Add to dashboard Cite

The extensive application of herbicides in crop cultivation has indisputably led to the emergence of weed populations characterized by multiple herbicide resistance (MHR). This phenomenon is associated with the enhanced metabolism and detoxifying ability of endogenous enzymes, such as phi class glutathione transferases (GSTFs). In the present work, a library of mutant GSTFs was created by in vitro directed evolution via DNA shuffling. Selected gstf genes from the weeds Alopecurus myosuroides and Lolium rigidum, and the cereal crops Triticum durum and Hordeum vulgare were recombined to forge a library of novel chimeric GSTFs. The library was activity screened and the best-performing enzyme variants were purified and characterized. The work allowed the identification of enzyme variants that exhibit an eight-fold improvement in their catalytic efficiency, higher thermal stability (8.3 °C) and three-times higher inhibition sensitivity towards the herbicide butachlor. The crystal structures of the best-performing enzyme variants were determined by X-ray crystallography. Structural analysis allowed the identification of specific structural elements that are responsible for kcat regulation, thermal stability and inhibition potency. These improved novel enzymes hold the potential for utilization in biocatalysis and green biotechnology applications. The results of the present work contribute significantly to our knowledge of the structure and function of phi class plant GSTs and shed light on their involvement in the mechanisms of MHR.

show abstract

Determination of Half-Maximal Inhibitory Concentration of an Enzyme Inhibitor

Cited by 8 publications

References 7 publications

Characterization of two β-galactosidases LacZ and WspA1 from Nostoc flagelliforme with focus on the latter’s central active region

Characterization of two β-galactosidases LacZ and WspA1 from Nostoc flagelliforme with focus on the latter’s central active region

Novel Drug Design for Treatment of COVID-19: A Systematic Review of Preclinical Studies

Directed Evolution of Phi Class Glutathione Transferases Involved in Multiple-Herbicide Resistance of Grass Weeds and Crops

Contact Info

Product

Resources

About