Original Article
Copyright ©2014 Baishideng Publishing Group Inc. All rights reserved.
World J Virology. Nov 12, 2014; 3(4): 30-36
Published online Nov 12, 2014. doi: 10.5501/wjv.v3.i4.30
Substrate specificity of avian influenza H5N1 neuraminidase
Naruthai Onsirisakul, Shin-ichi Nakakita, Chompunuch Boonarkart, Alita Kongchanagul, Ornpreya Suptawiwat, Pilaipan Puthavathana, Krisada Chaichuen, Kanokwan Kittiniyom, Yasuo Suzuki, Prasert Auewarakul
Naruthai Onsirisakul, Kanokwan Kittiniyom, Department of Clinical Microbiology and Applied Technology, Faculty of Medical Technology, Mahidol University, Bangkok 73170, Thailand
Naruthai Onsirisakul, Chompunuch Boonarkart, Ornpreya Suptawiwat, Pilaipan Puthavathana, Prasert Auewarakul, Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol Univeristy, Bangkok 10700, Thailand
Shin-ichi Nakakita, Division of Functional Glycomics, Life Sciences Research Center, Kagawa University, Takamatsu 761-0793, Japan
Alita Kongchanagul, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom 73170, Thailand
Krisada Chaichuen, Faculty of Veterinary Science, Mahidol University, Nakorn Pathom 73170, Thailand
Yasuo Suzuki, College of Life and Health Sciences, Chubu University, Kasugai 487-8501, Japan
Author contributions: Onsirisakul N preformed the majority of experiments; Nakakita S performed HPLC; Boonarkart C, Suptawiwat O and Kongchanagul A helped to perform and proved the constructs; Puthavathana P, Chaichuen K provided the viruses; Suzuki Y provided the glycopolymer; Kittiniyom K provided the supervision; Auewarakul P supervised and edited manuscript.
Supported by Thailand Research Fund, the Office of the Higher Education Commission and Mahidol University under the National Research Universities Initiative
Correspondence to: Prasert Auewarakul, Professor, Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol Univeristy, 2 Prannok Road, Bangkoknoi, Bangkok 10700, Thailand. sipaw@mahidol.ac.th
Telephone: +81-662-4198291 Fax: +81-662-4184148
Received: June 19, 2014
Revised: September 3, 2014
Accepted: October 14, 2014
Published online: November 12, 2014
Core Tip

Core tip: We analyzed neuraminidase (NA) substrate specificity of avian influenza H5N1 strains from humans and birds using a modified fluorescence assay, and the substrate specificity profile was further confirmed by high-performance liquid chromatography analysis of the enzymatic product. The H5N1 NA showed higher activity on α2,3-linkage. Interestingly, NA from an H5N1 human isolate that was previously shown to have heamagglutinin (HA) with dual specificity showed reduced activity on α2,3-linkage. These suggest that the H5N1 virus maintains the avian specific NA activity and that changes in the NA may be needed to compensate for changes in the HA specificity for the viral adaptation to human hosts.