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Udgivelsesdato: 1997-Mar-14 Human plasminogen, the inactive precursor of plasmin, exists in two major glycoforms. Plasminogen 1 contains an N-linked oligosaccharide at Asn-289 and an O-linked oligosaccharide at Thr-345. Plasminogen 2 is known to contain only an O-linked oligosaccharide at Thr-345. However, plasminogen 2 displays a further well documented microheterogeneity dependent on the N-acetylneuraminic acid content, which has functional consequences with regard to activation of plasminogen. The proposed structure and number of known oligosaccharide linkages in plasminogen 2 is insufficient to account for this microheterogeneity. In the present study, a combination of trypsin digestion, lectin affinity chromatography, Edman degradation amino acid sequence analysis, carbohydrate composition analysis, and mass spectrometry revealed the existence of a novel site for O-linked glycosylation on plasminogen 2 at Ser-248. Direct evidence for the structure of the carbohydrate was obtained from a combination of lectin affinity chromatography, desialylation experiments, and mass spectrometry analysis. These findings provide a structural basis for some of the observed microheterogeneity, and have implications with regard to the known functional consequences of the extent of sialylation of plasminogen.

15 holstein cows with a palpable uterine lumen (PUL) at first postpartum palpation were identified and each cow was matched with a normal cow for parity and stage of lactation. Blood was collected from each cow and the uterus cultured, flushed with lactated Ringer's solution and biopsied. Analysis of blood samples indicated that all cows were healthy. Bacteria were isolated form 14 of 15 PUL cows and 13 of 15 normal cows. Uterine flush analysis showed evidence of an inflammatory response in 5 PUL cows and 1 normal cow. Mean scores from microscopical examination of the biopsy specimens were greater in PUL cows, indicating increased pathologic changes in this group., The Bovine Practitioner, No. 29 (1995 September)