ریاضؔ خیرآبادی
ملک میں یہ خبر نہایت افسوس کے ساتھ سنی جائے گی کہ ہماری زبان کے مشہور کہنہ مشق اور استاد شاعر حضرت ریاض خیر آبادی نے نوے برس کی عمر میں ۱۷؍ ربیع الآخر کو وفات پائی، مرحوم اپنے صف سخن میں باکمال و بے مثال شاعرتھے، اﷲ تعالیٰ ان کو اپنی مغفرت کی شراب طہور سے سیراب فرمائے۔ (سید سلیمان ندوی، اگست ۱۹۳۴ء)
The wasaṭiyyah (Islamic moderation) concept is deep-rooted in Islam. It is a straight path, a good between two evils; it maintains balance between the two extremes of excess and deficiency, and between fanaticism and negligence. Moderation was widely practiced with the advent of Islam. It was a noteworthy aspect of people’s day to day life and conducts. The term wasaṭiyyah (moderation) emerged in the early eighties. It was initially introduced by Shiekh Yūsuf Al-Qaraḍāwī. He used it in his books and discourses, and gradually it become very prevalent. Few factors resulted in widespread use of the term, the main factor is the western systematic campaign against Islam and Muslims to distort their image and label them with terrorism and extremism. Therefore, they frequently used the term wasaṭiyyah to prove themselves against these accusations. Another factor is the current situation in most Muslim countries and their struggle with social and political injustice which turns Muslim youth to extremism and terrorism that is why Muslim scholars and reformers, through their moderate discourse, stood up and condemned fanaticism and radical ideology. All that made the term wasaṭiyyah widely used by different people from all walks of life, and each has its aims and intentions behind embracing the moderate discourse and raising the flag of wasaṭiyyah (moderation).
Alkaloids are produced in plants through various pathways involving several enzymes that lead to diverse alkaloids. One of the most important alkaloid biosynthetic enzymes is coclaurine N-methyltransferase (CNMT) which is an S-adenosyl-L- methionine-dependent methyltransferase (SAM-MTase). SAM-MTases utilize S- adenosyl-L-methionine (SAM) as a cofactor to methylate other molecules. CNMT catalyzes the methylation of coclaurine. Crystal structures of more than hundred SAM-MTases have been investigated. Several O-methyltransferases have been characterized at the molecular as well as structural levels, but there have been very few molecular studies of N-methyltransferases especially about CNMTs. In this study, the amino acids sequence of Aristolochia fimbriata putative CNMT has been determined by isolating and translating the full-length cDNA. In order to investigate the mechanism of methylation by this putative CNMT, three-dimensional homology model has been built and the ligand (SAM) as well as the substrate (S- Coclaurine) has been docked into its active site. Phylogenetic analyses were performed using the MEGA 4.0 software. The phylogenetic relationship of A. fimbriata putative CNMT with their homologs has also been analyzed. In order to identify the putative CNMT gene and determine its function, online similarity searches were performed by BLAST program using the cDNA sequence as well as the putative protein that could be encoded by the gene. All the methods, applied, predicted that the gene identified might be involved in the production of CNMT. The predicted homology model consists of two domains: the N-terminal catalytic core domain and the C-terminal domain. The catalytic core domain has a central sheet of β-strands surrounded by α helices. The catalytic core domain contains binding site for VSAM. The C-terminal domain consists of alpha helices and a few beta sheets creating a pocket for the substrate in between them. The SAM-binding pocket is located next to substrate binding pocket and there is an opening in between these two cavities through which the methyl group of SAM projects towards the substrate. The most important residues involved in the methyl transfer reaction seem to be Tyr-79 and Glu-96.