Research Article ISSN: 2574 -1241 DOI: 10.26717/BJSTR.2021.35.005677 Structure-Based Virtual Screening of Human β-Glucuronidase Inhibitors Sumera Zaib1*, Hadiqa Aimen2, Urooj Yousaf Virk1, Aliya Ibrar3, Asma Gul2, Muhammad Naveed4 and Imtiaz Khan5* 1Department of Biochemistry, Faculty of Life Sciences, University of Central Punjab, Pakistan 2Department of Biological Sciences, International Islamic University, Pakistan 3Department of Chemistry, Faculty of Natural Sciences, The University of Haripur, Pakistan 4Department of Biotechnology, Faculty of Life Sciences, University of Central Punjab, Pakistan 5Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom *Corresponding authors: Imtiaz Khan, Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom. Sumera Zaib, Department of Biochemistry, Faculty of Life Sciences, University of Central Punjab, Lahore-54590, Pakistan ARTICLE INFO ABSTRACT Received: April 14, 2021 Beta-glucuronidase is an important enzyme involved in the digestion, particularly Published: April 22, 2021 environmental toxins. Taking this into consideration, the present study was designed toin selectphase and2 of identifyliver detoxification potential scaffolds especially followed in detoxifying by beta-glucuronidase estrogen like hormonesinhibition and computational studies. Six different types of scaffolds were selected based on their Citation: Sumera Zaib, Hadiqa Aimen, potential to interact therapeutically with beta-glucuronidase enzyme. Among them, Urooj Yousaf Virk, Aliya Ibrar, Asma the most potent compound was subjected to molecular docking studies and the results Gul, Muhammad Naveed, Imtiaz Khan. Structure-Based Virtual Screening of site of beta-glucuronidase. Some compounds identical to marketed inhibitors of beta- revealed significant interactions with important amino acid residues within the active Human β-Glucuronidase Inhibitors. Biomed J Sci & Tech Res 35(2)-2021. was generated. The pharmacophore method was applied for the screening of potent glucuronidase were retrieved from PubChem and Zinc database, and a defined library BJSTR. MS.ID.005677. inhibitor of beta-glucuronidase. Structural similarity search feature assembled a total Keywords: Beta-Glucuronidase; Library the already reported methods. These investigations can be used in the design of selective - of >500 compounds. Out of which 9 compounds were selected and filtered out applying ing; Molecular Docking Design; Inhibitory Efficacy; Virtual Screen advancedβ-glucuronidase studies. inhibitors for future studies. This analysis may lead to findings for novel β-glucuronidase inhibitors against digestion related disorders after some more Introduction Glycosidase Family of Enzymes at specific glucuronide site [2]. These specific enzymes are found Glycosidases (GH) are vital for almost all living organisms categorized as one of the key enzymes for the treatment of numerous (exceptions are some Archaeans and a few unicellular parasitic in plants, bacteria and vertebrates. Intestinal β-glucuronidase is eukaryotes) playing diverse and different roles. Considering sp (Ampullaria and Helix pomatia) are used in the hydrolysis of intestinal diseases. In invertebrates, β-glucuronidase from mollusk the diversity of reactions, they catalyze, amino acid sequence steroids in order to assess urinary conjugate cortisol [3]. Besides categories [1]. been found active in acidic condition (pH ~ 4-5). It has also been and folding, glycosidases have been classified in many different intestinal β-glucuronidase, the lysosomal β-glucuronidase have Beta-Glucuronidases observed that there is a direct effect of pH and temperature on the glycosidase that have role in the hydrolysis of glycosaminoglycans stability of enzyme. The stability of β-glucuronidase is determined Beta-glucuronidase (β-glucuronidase) enzyme (EC3.2.1.31) is a standard (37 °C) and optimum temperature (70 °C). At both and confirmed by residual activity at varying temperature of Copyright@ Sumera Zaib, Imtiaz Khan | Biomed J Sci & Tech Res | BJSTR. MS.ID.005677. 27515 Volume 35- Issue 2 DOI: 10.26717/BJSTR.2021.35.005677 temperatures, the enzymes have a positive response from acidic mass of 50 KDa [7]. to neutral pH. At 75 °C temperature and pH above 8, the activity Structure of Beta-Glucuronidases carbohydrate processing. Human beta-glucuronidase is found to be as 80 kDa in of enzyme is lost [3]. Other key roles of β-glucuronidase includes monomeric form (653 amino acids residues) and its proteolysis They also show functional importance and are used in the cleaves 18 amino acid residues from the carboxy terminal end hydrolysis of various steroids, bioassay for plant hormones, leaving it as 78 kDa monomer. It exists in homotetrameric form prodrug therapy [4] and as biomarker [5] and are present in with 332 kDa while carrying various notable structural changes, including beta barrel type, also known as a jelly-roll barrel, and extracellular fluid during the inflammation [6]. In human plasma, the TIM barrel [8]. The crystal structure of the enzyme has been β-glucuronidase serves as a biomarker for the identification this enzyme can lead to autosomal recessive disorders which is of human exposure to organophosphate [4]. The deficiency of mucopolysaccharidosis VII, commonly known as Sly syndrome solved by X-ray crystallography. The specific site for the transport (MPR) [9]. of lysosomal β-glucuronidase is mannose 6-phosphate receptor (GUSB) plays an important role in various applications of plant Chromosomal Location of Beta-Glucuronidases GAUSB [4]. Genetic studies have revealed that β-glucuronidase gene Gene biotechnology. β-Glucuronidase proteins have also been developed Its cytogenetic location is 7q11.21, on the long (q) arm of replacement therapy). The protein, isolated from most vertebrates, by cloning, expression and purification of enzymes (enzyme chromosome, number 7 at 11.21 position (Figure 1) while its occurs in the form of homotetramers with a molecular mass of molecular location is 65,960,684 to 65,982,314 base pairs on chromosome number 7 (Homo sapiens Annotation Release 109, by various chromatographic techniques possesses a molecular around 280-300 KDa while the lysosomal β-glucuronidase purified GRCh38.p12) (NCBI). Figure 1: Chromosomal location of GAUSB gene (NCBI). Beta-glucuronidase and Diseases Computational Screening In 2000, Sperker et al. addressed the least investigated issue Virtual screening (VS) is a powerful computer-based technique regarding the excess release of beta-glucuronidase in pancreatic cancer [10]. This fatal pancreatic cancer is world’s 5th cause which has widely been used for the identification of promising of death. This study illustrated the excess release of enzyme by with known molecular target structures. VS is considered as an compounds such as specific inhibitors that are capable of binding carcinoma cells as compared to normal cells. It is also up regulated in imperative technique, for new inhibitors and molecular drug different pathological diseases like urinary tract infection and renal discovery, depending upon the growing demand of protein and diseases. It also causes transplant rejection, epilepsy and cancers nucleic acid structure. Virtual screening evaluates numerous i-e., breast and larynx cancer. Moreover, it is involved in the bone understood and perceived for this purpose. Primary concern is compounds all at once, two significant steps should be well arthritis, and several hepatic diseases, and later acquired related disorders like inflammatory joint disorder and rheumatoid to find docking technique which will enable us to acquire our experiments of redocking are accomplished, where separation of immunodeficiency syndrome which is linked to the overexpression desired configuration [13]. To justify a docking method, various whole series of known complexes are completed followed by the of beta-glucuronidase [11]. In many tumors and inflammatory into the extracellular space [10]. Since then, the researchers started process of redocking. The secondary concern is to assure whether areas, β-glucuronidase activity is high and the enzyme is secreted focusing the inhibition of beta-glucuonidase enzyme through the this docking strategy will be able to replicate the detected binding development of various inhibitors mainly nitrogen heterocyclic mode. Through these validation studies, nearly 10 degree of compounds such as indole, triazoles and benzothiazole [12]. torsional freedom was found in drug like molecules of recent version Copyright@ Sumera Zaib, Imtiaz Khan | Biomed J Sci & Tech Res | BJSTR. MS.ID.005677. 27516 Volume 35- Issue 2 DOI: 10.26717/BJSTR.2021.35.005677 of Auto-Dock. Furthermore, next step is to ensure experimentally Docking Based Screening (DBVS) that the compounds do bound at their predicted binding energy, allowing precise grading of compounds [13]. presented below functions normally using targeted structure The workflow chart for docking-based virtual screening (DBVS) for input, which can be modelled experimentally or on computer of energy prediction through computational based docking basis together with small-molecules containing compound library Solely standard deviation of 2-3 Kcal/mol, provides efficiency which is either purchased or synthesized (Figure 2). Proper ranking though. The compound enrichment process is implied assignment of protonation, tautomeric, and stereoisomeric states algorithms