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The nine-banded armadillo (Dasypus novemcinctus mexicanus Peters) was chosen for this study so that a comparison could be made of the salivary mucus glycoproteins of an ancient mammalian species with those derived from previously studied, more highly evolved species. Two mucus glycoproteins, armadillo submandibular glycoprotein A and armadillo submandibular glycoprotein B, were prepared from the armadillo submandibular gland by a modification of the method of Tettamanti & Pigman (1968) (Arch. Biochem. Biophys. 124, 41-50). The composition of glycoprotein A is the simplest one among the known mucus glycoproteins. Six amino acids constitute 98.5 mol/100mol of the protein of glycoprotein A and 82 mol/100 mol of that of glycoprotein B. These are serine and threonine (which make up 40-50% of the molar amino acid composition), glutamic acid, glycine alanine and valine. Proline is absent from glycoprotein A and comprises only 2.3% of glycoprotein B. For both glycoproteins, the protein content, as determined by the method of Lowry, Rosebrough, Farr & Randall (1951) (J. Biol. Chem 193, 265-275), with bovine serum albumin as standard, was nearly 60% higher than when determined by the sum of the amino acids. The ratios of total mol of amino acid/total mol of carbohydrate are 1:0.63 for glycoprotein A and 1:0.68 for glycoprotein B, N-Acetylneuraminic acid and N-acetylgalactosamine, in a molar ratio of about 0.35:1.00, are the principal carbohydrates present in both glycoproteins. Neutral sugars seem to be absent from glycoprotein A, but galactose and fucose are present in glycoprotein B. The carbohydrate side chains in glycoprotein A are composed of about two-thirds monosaccharide and one-third disaccharide residues, whereas those of glycoprotein B are more complex. For both glycoproteins, essentially all of the N-acetylgalactosamine was attached O-glycosidically to the hydroxyamino acid residues of the protein core. The linkage of N-acetylneuraminic acid glycoprotein A was extremely sensitive to dilute acid and neuraminidase. Glycoprotein B has chemical properties similar to those of glycoprotein A. However, whereas glycoprotein A was susceptible to both Clostridium perfringens and Vibrio cholerae neuraminidases, only the latter enzyme had an effect on glycoprotein B at pH 4.75. Both glycoproteins were homogeneous by cellulose acetate electrophoresis and ultracentrifugal analyses. The apparent mol.wts. of glycoprotein A and glycoprotein B were 7.8 X 10(4) and 3.1 X 10(4) respectively.

Twenty-four hour urinary total hydroxyproline was measured in 70 normal males and 10 normal females between the ages of 5 through 49. Normal values for excretion of hydroxyproline were found to vary markedly with age and correlated well with periods of growth.

RECENT work has shown that the permeability of capillary blood vessel walls does not seem to be affected by scurvy1despite the presence of hæmorrhages. However, capillary resistance was shown to decrease2–6and the corresponding capillary fragility increased6,7. No investigations of the influence of scurvy on the permeability of dermal and connective tissue have been made.

Long-term methandrostenolone therapy was associated with a markedly lowered hydroxyproline excretion and increased physical well-being in a 36-year-old patient with Marfan's syndrome. It is suggested that the anabolic steroid favorably affected collagen metabolism in this patient.

A CONVENIENT method for the isolation of bovine submaxillary mucin in a relatively undegraded and homogeneous state compared to earlier methods1has been developed in this Laboratory. Fresh glands (640 gm.) were ground and stirred mechanically with three changes of 500 ml. of cold water for a total of 54 hr. The pooled extracts were clarified by centrifuging at 26,3600g for 30 min. and adjusted to pH. 3.5. The resulting mucin clot was separated and dissolved in cold water by neutralization to 7.5, and lyophilized. The product was purified by solution in 500 ml. of cold 50 per cent (w/v) aqueous calcium chloride. After centrifugation at 26,360g for 30 min., the supernatant was fractionated with cold ethanol. The fraction separating at 60–75 per cent (v/v) ethanol was collected by centrifugation at 26,360g for 30 min., dissolved in water, dialysed against water and lyophilized. All procedures were carried out at 0–4° C. The yield was 0.64 and 2.5 per cent of the glands on fresh and dry weight basis, respectively. The recovery of sialic acid was 36 and 60 per cent of that in the extract and mucin clot, respectively. A repetition of the procedure did not alter the composition of the product. The lyophilized powder could be stored at 2–4° C. without change of its properties.