Suri S. Iyer

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Name: Iyer, Suri S.
Organization: Georgia State University , USA
Department: Department of Chemistry
Title: Associate(PhD)

TOPICS

Co-reporter:Xikai Cui;Hieu Dinh;Yun He;Bharat P. Gurale;Abasaheb N. Dhawane;Venkatachalam Udhayakumar;Naomi W. Lucchi
Bioconjugate Chemistry December 21, 2016 Volume 27(Issue 12) pp:2886-2899
Publication Date(Web):October 28, 2016
DOI:10.1021/acs.bioconjchem.6b00542
Co-reporter:Xikai Cui;Amrita Das;Abasaheb N. Dhawane;Joyce Sweeney;Xiaohu Zhang;Vasanta Chivukula
Chemical Science (2010-Present) 2017 vol. 8(Issue 5) pp:3628-3634
Publication Date(Web):2017/05/03
DOI:10.1039/C6SC03720H
Rapid and precise detection of influenza viruses in a point of care setting is critical for applying appropriate countermeasures. Current methods such as nucleic acid or antibody based techniques are expensive or suffer from low sensitivity, respectively. We have developed an assay that uses glucose test strips and a handheld potentiostat to detect the influenza virus with high specificity. Influenza surface glycoprotein neuraminidase (NA), but not bacterial NA, cleaved galactose bearing substrates, 4,7di-OMe N-acetylneuraminic acid attached to the 3 or 6 position of galactose, to release galactose. In contrast, viral and bacterial NA cleaved the natural substrate, N-acetylneuraminic acid attached to the 3 or 6 position of galactose. The released galactose was detected amperometrically using a handheld potentiostat and dehydrogenase bearing glucose test strips. The specificity for influenza was confirmed using influenza strains and different respiratory pathogens that include Streptococcus pneumoniae and Haemophilus influenzae; bacteria do not cleave these molecules. The assay was also used to detect co-infections caused by influenza and bacterial NA. Viral drug susceptibility and testing with human clinical samples was successful in 15 minutes, indicating that this assay could be used to rapidly detect influenza viruses at primary care or resource poor settings using ubiquitous glucose meters.
Co-reporter:Bharat P. Gurale, Abasaheb N. Dhawane, Xikai Cui, Amrita Das, Xiaohu Zhang, and Suri S. Iyer
Analytical Chemistry 2016 Volume 88(Issue 8) pp:4248
Publication Date(Web):March 18, 2016
DOI:10.1021/acs.analchem.5b03943
Glycosidases are essential enzymes that cleave glycoside bonds. The presence of glycosidases have been widely used to detect pathogens, label cells/tissues, and report specific diseases. We have developed a rapid electrochemical assay to detect glycosidases. Exposure of electrochemically inactive substrates to glycosidases releases glucose, which can be measured easily using an electrochemical cell. Five different glycosidases were detected rapidly within 1 h using disposable electrodes. This assay could readily be incorporated into repurposed glucose meters to rapidly detect glycosidases, which in turn could be useful to report the presence of a pathogen or illness.
Co-reporter:Yun He, Yang Yang, and Suri S. Iyer
Bioconjugate Chemistry 2016 Volume 27(Issue 6) pp:1509
Publication Date(Web):May 3, 2016
DOI:10.1021/acs.bioconjchem.6b00150
We report the synthesis of influenza virus neuraminidase (NA) resistant sialosides that include different glycoside linkages (C-, S-, and triazole). These unnatural sialosides were printed onto glass slides to generate a small focused microarray. We evaluated the binding affinity of multiple lectins and compared the stability of these sialosides with O-linked sialosides toward influenza virus neuraminidase and intact virus. We demonstrated the ability of these molecules to capture eight different strains of influenza virus at ambient temperature without the addition of NA inhibitors. The glycans capture extremely low, clinically relevant concentrations of viruses and each strain gives rise to a specific “fingerprint” binding pattern, which could potentially be used in rapid diagnostic tests.
Co-reporter:Abasaheb N. Dhawane, Marta Diez-Valcarce, Bharat P. Gurale, Hieu Dinh, Jan Vinjé, and Suri S. Iyer
Bioconjugate Chemistry 2016 Volume 27(Issue 8) pp:1822
Publication Date(Web):July 6, 2016
DOI:10.1021/acs.bioconjchem.6b00226
A panel of biotinylated bivalent H-type glycans that have been reported as binding ligands for human noroviruses were synthesized using a modular synthetic strategy. These glycoconjugates were attached to streptavidin-coated magnetic beads and used to recover human norovirus from fecal samples using a magnetic bead-based assay. The biotinylated bivalent glycans synthesized for this study exhibited similar or better capturing ability when compared to commercial biotinylated glycopolymers.
Co-reporter:Xiaohu Zhang;Dr. Abasaheb N. Dhawane;Joyce Sweeney;Dr. Yun He;Dr. Mugdha Vasireddi ; Suri S. Iyer
Angewandte Chemie 2015 Volume 127( Issue 20) pp:6027-6030
Publication Date(Web):
DOI:10.1002/ange.201412164

Abstract

An electrochemical assay has been designed to rapidly diagnose influenza viruses. Exposure of a glucose-bearing substrate to influenza viruses or its enzyme, neuraminidase (NA), releases glucose, which was detected amperometrically. Two methods were used to detect released glucose. First, we used a standard glucose blood meter to detect two viral NAs and three influenza strains. We also demonstrated drug susceptibility of two antivirals, Zanamivir and Oseltamivir, using the assay. Finally, we used disposable test strips to detect nineteen H1N1 and H3N2 influenza strains using this assay in one hour. The limit and range of detection of this first generation assay is 102 and 102–108 plaque forming units (pfu), respectively. Current user-friendly glucose meters can be repurposed to detect influenza viruses.

Co-reporter:Xiaohu Zhang;Dr. Abasaheb N. Dhawane;Joyce Sweeney;Dr. Yun He;Dr. Mugdha Vasireddi ; Suri S. Iyer
Angewandte Chemie International Edition 2015 Volume 54( Issue 20) pp:5929-5932
Publication Date(Web):
DOI:10.1002/anie.201412164

Abstract

An electrochemical assay has been designed to rapidly diagnose influenza viruses. Exposure of a glucose-bearing substrate to influenza viruses or its enzyme, neuraminidase (NA), releases glucose, which was detected amperometrically. Two methods were used to detect released glucose. First, we used a standard glucose blood meter to detect two viral NAs and three influenza strains. We also demonstrated drug susceptibility of two antivirals, Zanamivir and Oseltamivir, using the assay. Finally, we used disposable test strips to detect nineteen H1N1 and H3N2 influenza strains using this assay in one hour. The limit and range of detection of this first generation assay is 102 and 102–108 plaque forming units (pfu), respectively. Current user-friendly glucose meters can be repurposed to detect influenza viruses.

Co-reporter:Hieu Dinh, Xiaohu Zhang, Joyce Sweeney, Yang Yang, Yun He, Abasaheb Dhawane, and Suri S. Iyer
Analytical Chemistry 2014 Volume 86(Issue 16) pp:8238
Publication Date(Web):July 9, 2014
DOI:10.1021/ac501624v
We have developed a panel of synthetic glycans as receptor mimics for the specific capture of influenza viruses. The glycans were printed onto commercial glass slides using a free amine at the end of a spacer to generate a small focused microarray. The microarray was evaluated for its ability to capture three different strains of influenza A virus, two H1N1, A/Brisbane/59/2007 and A/Solomon Islands/3/2006 and one H3N2, A/Aichi/2/1968. We observed an excellent detection ability with some compounds exhibiting clinically relevant (101 plaque forming units) limit of detection. We also tested the drug susceptibility of current antivirals, Zanamivir and Ostelamivir using this microarray and could determine antiviral resistance for these strains.
Co-reporter:Yang Yang, Yun He, Xingzhe Li, Hieu Dinh, Suri S. Iyer
Bioorganic & Medicinal Chemistry Letters 2014 Volume 24(Issue 2) pp:636-643
Publication Date(Web):15 January 2014
DOI:10.1016/j.bmcl.2013.11.077
We have synthesized a panel of bivalent S-sialoside analogues, with modifications at the 4 position, as inhibitors of influenza virus. These first generation compounds show IC50 values ranging from low micromolar to high nanomolar in enzyme inhibition and plaque reduction assays with two intact viruses, Influenza H1N1 (A/California/07/2009) and H3N2 (A/Hongkong/8/68).
Co-reporter:Hailemichael O. Yosief; Alison A. Weiss; Suri S. Iyer
ChemBioChem 2013 Volume 14( Issue 2) pp:251-259
Publication Date(Web):
DOI:10.1002/cbic.201200582

Abstract

Biotinylated mono- and biantennary di-/trisaccharides were synthesized to evaluate their ability to capture E. coli strains that express pilus types with different receptor specificities. The synthesized biotinylated di-/trisaccharides contain Galα(14)Gal, Galα(14)GalNHAc, GalNHAcα(14)Gal, Galα(14)Galβ(14)Glc and GalNHAcα(14)Galβ(14)Glc as carbohydrate epitopes. These biotinylated oligosaccharides were immobilized on streptavidin-coated magnetic beads, and incubated with different strains of live E. coli. Capturing ability was assessed by using a luciferase assay that detects bacterial ATP. The trisaccharides containing Galα(14)Galβ(14)Glc and the disaccharides containing Galα(14)Gal as the epitopes exhibited strong capturing ability for uropathogenic E. coli strains with the pap pilus genotype, including CFT073, J96 and J96 pilE. The same ligands failed to capture E. coli strains with fim, prs, or foc genotypes. Uropathogenic CFT073 was also captured moderately by biantennary disaccharides containing a GalNHAc moiety at the reducing end; however, other saccharides containing GalNHAc at the nonreducing end did not capture the CFT073 strain. These synthetic glycoconjugates could potentially be adapted as rapid diagnostic agents to differentiate between different E. coli pathovars.

Co-reporter:Xikai Cui, Amrita Das, Abasaheb N. Dhawane, Joyce Sweeney, Xiaohu Zhang, Vasanta Chivukula and Suri S. Iyer
Chemical Science (2010-Present) 2017 - vol. 8(Issue 5) pp:
Publication Date(Web):
DOI:10.1039/C6SC03720H
2,3,4,6-Tetra-O-acetyl-D-glucopyranosyl trichloroacetimidate
β-D-Galactopyranoside, 2-[2-(2-azidoethoxy)ethoxy]ethyl, 2,3,4,6-tetraacetate
a-D-Mannopyranose,2,3,4,6-tetraacetate 1-(2,2,2-trichloroethanimidate)
6-chlorohexanal
1,4,10-Trioxa-7,13-diazacyclopentadecane
1-Octyne, 8-chloro-