Green Tea Catechins Inhibit Bacterial DNA Gyrase by Interaction with Its ATP Binding Site

Abstract

Catechins are the main ingredients of green tea extracts and have been shown to possess versatile biological activities, including antimicrobial. We determined that the catechins inhibit bacterial DNA gyrase by binding to the ATP binding site of the gyrase B subunit. In the group of four tested catechins, epigallocatechin gallate (EGCG) had the highest activity, followed by epicatechin gallate (ECG) and epigallocatechin (EGC). Specific binding to the N-terminal 24 kDa fragment of gyrase B was determined by fluorescence spectroscopy and confirmed using heteronuclear two-dimensional NMR spectroscopy of the EGCG-15N-labeled gyrase B fragment complex. Protein residues affected by binding to EGCG were identified through chemical shift perturbation. Molecular docking calculations suggest that the benzopyran ring of EGCG penetrates deeply into the active site while the galloyl moiety anchors it to the cleft through interactions with its hydroxyl groups, which explains the higher activity of EGCG and ECG.

Análise dos efeitos da epigalocatequina-3-galato (EGCG) de Camellia sinensis (chá verde) em modelo de hepatotoxicidade química experimental induzida pela Dietilnitrosamina (DEN)

“…Especificamente, as atividades inibitórias foram observadas em reações com: proteína quinase C, peroxidação lipídica, angiogênese, formação de radicais livres, descarboxilase de ornitina, uroquinase, lipoxigenase, cicloxigenase, DNA polimerase, DNA topoisomerase, DNA girase, Bcl-2, ERK1/2 e quinase AKT, ácido graxo sintase, p-hidróxibenzoato hidroxilase, epoxidase escaleno, dopa descarboxilase, esteróide 5-α redutase, β-catenina, P-glicoproteína, receptor de fator de crescimento tipo insulina-1, telomerase, proteassomo e vários tipos de proteases (ABE et al, 2000;BERTOLDI;GONSALVI;VOLTATTORNI, 2001;DASHWOOD;ORNER;DASHWOOD, 2002;FUJIKI, 1999;GRADISAR et al, 2007;JODOIN;DEMEULE;BELIVEAU, 2002;LEONE et al, 2003;NAM;SMITH;DOU, 2001;SAH et al, 2004;SHIMIZU et al, 2005;TOSETTI et al, 2002;TIAN, 2001). As atividades indutivas foram encontradas em enzimas de fase II (GST), GSH-Px, catalase, NAD(P)H, quinonaredutase e junção de intervalo (FUJIKI, 1999).…”

A Comparative Study of the Antibacterial Efficacy of two Natural Irrigating Solutions with Two Different Root Canal Sealers on E-feacalis

“…Green tea has antimicrobial activity on E fecalis and found to be a good chelating agent (4,5) . On other hand Propolis exhibits a wide range of biologic activities, including antimicrobial, anti-inflammatory, antioxidant, anesthetic and cytotoxic properties (6) .…”

“…4,No. 4 obtained by Clegg et al showing that they tested only the antimicrobial activity of the agents, but not their capacity to disrupt the biofilm structure; and the SEM analysis was conducted only to confirm the presence of the biofilm on dentin surface and its removal by the glass beads (35) .…”

Spectroscopic Properties of Quercetin in AOT Reverse Micelles

“…Flavonoids are widely distributed in fruits and vegetables, and have been received a great deal of attention due to their many biological properties, i.e., anticarcinogenic, antiatherosclerotic, antimicrobial, and antioxidant properties. [1][2][3][4][5][6] QCT is remarkable for its properties to mitigate the increase in capillary fragility, to reduce high blood pressure, to protect plants against the direct and indirect influences of UV radiation and to show antioxidant behaviors against a wide range of free radicals. [7][8][9][10][11][12] Flavonoids are well known compounds that exhibit characteristic fluorescence properties.…”