Plasmodium falciparum malaria parasites with different capabilities of invading sialic acid-deficient erythrocytes were identified. Thai-2 parasites cultured in Tn erythrocytes invaded neuraminidase-treated and Tn erythrocytes twice as efficiently as Thai-2 parasites cultured in normal erythrocytes and seven to ten times more efficiently than a cloned line of Camp parasites cultured in normal e...

Neuraminidase inhibitors (NAIs) are first-line agents for the treatment and prevention of influenza virus infections. As for other antivirals, the development of resistance to NAIs has become an important concern particularly in the case of A(H1N1) viruses and oseltamivir. The most frequently reported change conferring oseltamivir resistance in that viral context is the H275Y neuraminidase muta...

Recent outbreaks of highly pathogenic and occasional drug-resistant influenza strains have highlighted the need to develop novel anti-influenza therapeutics. Here, we report computational and experimental efforts to identify influenza neuraminidase inhibitors from among the 3000 natural compounds in the Malaysian-Plants Natural-Product (NADI) database. These 3000 compounds were first docked int...

Bound sialic acids on rat spermatozoa were assayed by oxidation with 1 mMNaIO4 at 0\s=deg\C,liberating C-9 as formaldehyde which was further quantitated using 3\x=req-\ methyl-2-benzothiazolinone. The mean \m=+-\s.d. (n = 20) content of bound sialic acids of spermatozoa from the caput and cauda epididymidis was 50\m=.\9 \m=+-\8\m=.\0and 25\m=.\2 \m=+-\3\m=.\8 nmol/108 spermatozoa respectively. ...

Newcastle disease virus isolates from chickens in eastern Uganda in 2001 were found to be velogenic by fusion protein cleavage site sequence analysis and biological characterization; the intracerebral pathogenicity index was 1.8. Analysis of their hemagglutinin-neuraminidase protein gene sequences revealed a novel genotype unrelated to those that caused previous outbreaks.

We investigated a family in which some individuals showed extremely high serum leucine aminopeptidase (LAP) (EC 3.4.11.2) activity, mainly derived from a variant CD13. The isoelectric points of the variant and normal CD13 were 3.3 and 4.1, respectively, and both points converged at 4.4 after treatment with neuraminidase, indicating that more sialic acids are bound to the variant CD13 than norma...

Continuing occurrences of human infections with avian influenza A (H5N1) viruses have ignited increasing fears that the next influenza pandemic is imminent. Fortunately, options for antiviral prophylaxis and treatment have been improved dramatically since the previous pandemics by the availability of neuraminidase inhibitors such as zanamivir and oseltamivir. However, although the prophylactic ...

During a search for neuraminidase inhibitors derived from medicinal fungi, we found that the fermentation broth of Phellinus linteus exhibited potent neuraminidase inhibitory activity. Through bioassay-guided fractionation, two active compounds were purified from the ethyl acetate-soluble portion of the fermentation broth of P. linteus. These structures were identified as inotilone (1) and 4-(3...

A selective and potent inhibitor of neuraminidases, a hydrolase that is responsible for processing sialylated glycoconjugates, is a promising drug candidate for various infective diseases. The current study demonstrates that the use of an aglycone-focused library of 2-difluoromethylphenyl α-sialosides is an effective technique to find potent and selective mechanism-based labeling reagents for n...

Influenza viruses possess at their surface two glycoproteins, the hemagglutinin and the neuraminidase, of which the antagonistic functions have to be well balanced for the virus to grow efficiently. Ferraris et al. isolated in 2003-2004 viruses lacking both a NA gene and protein (H3NA- viruses) (Ferraris O., 2006, Vaccine, 24(44-46):6656-9). In this study we showed that the hemagglutinins of tw...