Neuraminidase inhibitor assay requiring complicated step-by-step operation was successfully integrated into ”Single-Step” by using CPC sensor. We developed a combinable PDMS capillary (CPC) sensor for enzyme inhibition assay using the concave and convex type PDMS substrates. In the conventional enzyme inhibitor assay, complicated analytical procedures, such as mixing and dissolution, are requir...

Neuraminidase activity has been found in a variety of strains of Corynebacterium diphtheriae, both toxinogenic and nontoxinogenic. The enzyme has been shown to be intracellular, possibly associated with the cytoplasmic membrane. Toxinogenic strains of the diphtheria bacillus, grown under conditions unsuitable for maximal toxin production, produce neuraminidase, and the enzyme has been purified ...

The elective isolation of a soil microorganism, tentatively assigned to the genus Arthrobacter, which produced an extracellular neuraminidase is described. The secretion of neuraminidase from washed cells in minimal medium required the presence of sialo-containing glycoproteins, whereas free N-acetyl-neuraminic asid of N-acetylmannosamine were poor inducers. No enzyme could be dected in the ind...

OBJECTIVES We characterized human H1N1 influenza isolate A/Hokkaido/15/02, which has haemagglutinin and neuraminidase mutations that reduce drug susceptibility to oseltamivir, zanamivir and peramivir. METHODS One wild-type and three mutant viruses were isolated by plaque purification. Viruses were tested in MUNANA-based enzyme assays, cell culture and receptor binding assays. RESULTS Two vi...

The contribution of influenza A neuraminidase antibodies to the reaction with whole virus in an enzyme-linked immunosorbent assay (ELISA) was assessed by specific absorption of rabbit hyperimmune sera. Although measurable and independent, the effect of neuraminidase antibodies was less than that of hemagglutinin antibodies. Recombinants with an irrelevant hemagglutinin were used successfully as...

The fluorometric neuraminidase assay method using 4-methylumbelliferyl-N-Ac-aD-neuraminide as a substrate was investigated for the purpose of ascertaining its validity as a procedure for influenza viral neuraminidase antibody inhibition test. The enzyme antibody inhibition titer obtained by the fluorometric assay system was far weaker than that obtained by the standard colorimetric neuraminidas...

A gene from Streptococcus pneumoniae was cloned in lambda EMBL301 and then expressed in Escherichia coli, which cleaved the fluorogenic neuraminidase substrate 2'-(4-methylumbelliferyl)-alpha-d-N-acetylneuraminic acid. The cloned gene therefore encodes an enzyme with neuraminidase activity. On the basis of restriction mapping and DNA hybridization studies, this gene could be distinguished from ...

Neuraminidaseis a key enzyme in the life cycle of influenza viruses and is present in some bacterial pathogens. We here assess the inhibitory potency of plant tannins versus clinically used inhibitors on both a viral and a bacterial model neuraminidase by applying the 2'-(4-methylumbelliferyl)-α-d-N-acetylneuraminic acid (MUNANA)-based activity assay. A range of flavan-3-ols, ellagitannins and ...

The enzymes neuraminidase (EC 3.2.1.18) and acylneuraminate pyruvate lyase (EC 4.1.3.3) were found in a strain of vibrio falling into Heiberg's group II isolated from a patient with diarrhea. The neuraminidase of this strain resembles the neuraminidase of Vibrio cholerae. The pH-optimum, activation by Ca-ions and heat inactivation were studied. There is also some indication of an immunologicall...