Mesosomes in Pseudomonas aeruginosa.

The use of a combination fixative-staining procedure has allowed a detailed observation of mesosomes in thin sections of Pseudomonas aeruginosa.

Ultrastructural alterations associated with the growth of resistant Pseudomonas aeruginosa in the presence of benzalkonium chloride.

Cells of Pseudomonas aeruginosa resistant to benzalkonium chloride (BC) underwent unique ultrastructural reorganizations when they were grown in the presence of 1 mg of BC/ml. The resistant cells usually contained a single, centrally positioned pseudovacuole. The pseudovacuole was surrounded by a diffuse substance that spread irregularly throughout the cytoplasm.

Biosynthesis of streptococcal cell walls: N-acetyl-D-muramic acid.

Glucose-1-(14)C and acetylglucosamine-1-(14)C were added singly and together with equal amounts of the unlabeled reciprocal to Brain Heart Infusion and used for the culture of Streptococcus pyogenes. The labeling pattern of the rhamnose, glucosamine, and muramic acid in the cell wall supported an intermediary role for acetylglucosamine in providing the C1-C6 moiety of muramic acid. Although radioactivity in the C2-C9 portion of muramic acid suggested that some of the lactyl group (C7-C9) came from glycolytic products, there was also considerable contribution to it from noncarbohydrate sources.