Previous studies have shown that Sindbis virus, an enveloped alphavirus of the togavirus group, activates the alternative complement pathway in the absence of detectable antiviral immunoglobulin. The present studies examined the role of the host-determined sialic acid content of Sindbis virus on activation of the alternative complement pathway. Purified Sindbis virus grown in baby hamster kidne...

We have previously engineered transgenic insect cell lines to express mammalian glycosyltransferases and showed that these cells can sialylate N-glycoproteins, despite the fact that they have little intracellular sialic acid and no detectable CMP-sialic acid. In the accompanying study, we presented evidence that these cell lines can salvage sialic acids for de novo glycoprotein sialylation from...

Sialic acids are a family of amino sugars that are commonly found as terminal oligosaccharide residues on glycoproteins and glycolipids. Plasma lipoproteins are sialylated on their apolipoprotein and glycolipid constituents. The function of sialic acid on apolipoproteins is not completely understood but has been associated with secretion, lipid-binding, and plasma clearance for some apolipoprot...

Many human-dwelling bacteria acquire sialic acid for growth or surface display. We identified previously a sialic acid utilization operon in Tannerella forsythia that includes a novel outer membrane sialic acid-transport system (NanOU), where NanO (neuraminate outer membrane permease) is a putative TonB-dependent receptor and NanU (extracellular neuraminate uptake protein) is a predicted SusD f...

BACKGROUND In animal studies, sialic acid supplementation is associated with increases of gangliosides in the brain and improved learning ability. Only limited data are available on the sialic acid content of human milk and infant formulas. OBJECTIVE We compared the concentrations of oligosaccharide-bound, protein-bound, and free sialic acid in milk from mothers of full-term and preterm infan...

OBJECTIVE Serum sialic acid has recently gained interest as a possible cardiovascular risk factor as well as a potential tumour marker. The effect of pregnancy on serum sialic acid is unclear particularly in the post-partum period. DESIGN Longitudinal cohort. SETTING Teaching hospital antenatal clinic. POPULATION 29 pregnant women, 27 age matched non-pregnant women. METHODS Specific enz...

BACKGROUND It is known that tissue and serum sialic acid levels may be altered by malignant transformation. In this study, sialic acid levels were determined in bronchoalveolar lavage fluid (BAL) and serum in two groups of patients with lung cancer and non-malignant diseases of the lung. METHODS Colorimetric methods were used for determination sialic acid in serum and in BAL samples. Flexible...

Biological membranes are complex systems which have attracted scientific interest for a long time and for various reasons. The sialic acid-liposome interactions at the molecular level depend on their hydro-lipophilic characteristics. The aim of the present study was to investigate the changes of conformation of the phospholipid (1,2-Diacyl-sn-glycero-3-phosphocholine) and sialic acid (2,8-(N-ac...

Introduction Sialic acid (N-acetylneuraminic acid, NeuAc, Neu5Ac) is an essential terminal sugar on the glycan moieties of many functional and structural human glycoproteins. A key intermediate in the biochemical process to form sialic acid is the monosaccharide, ManNAc, which is formed by the bifunctional enzyme UDPN-acetylglucosamine / Nacetylmannosamine epimerase kinase (GNE). ManNAc is an i...

The reaction of colloidal iron hydroxide (CIH) with acidic groups was applied for an ultrastructural study of the distribution of sulphuric acid monoesters and sialic acid in synaptic vesicles and external nerve ending membranes isolated from rat brain. At pH 1-7 CIH was precipitated as electron-dense granules with a uniform size of 6—7 nm specifically labelling the carboxyl group of sialic aci...