Gram stain reaction

Histochemistry of the Gram-staining Reaction for Micro-organisms, H. Henry and M. Stacey, Nature, 151 (1943)671. 

Aside from physical appearance and Gram-stain reaction, physiological tests for identification of LAB center, initially, on the differences between the two pathways of sugar utilization. Wine LAB include both heterofermenters and homofermenters. Leuconostoc oenos and its strains are hetero-fermentative, whereas Pediococcus is homofermentative and the lactobacilli may be found in both groups. 

The test for catalase and, hence, oxidative metabolism is easily accomplished and, along with Gram stain reaction, provides valuable information regarding the bacteria s identity. 

Hugo, W. B. Longworth, A. R. (19646). Effect of Chlorhexidine on protoplasts and spheroplasts of E. coli, protoplasts of B. megaterium and the Gram staining reaction of Staph, aureus. J. Pharm. Pharmacol, 16, 751-8. 

Recent Advances in Microbiological Methods. Chemistry of Gram Staining and of the Feulgen and Dische Reactions for Nuclear Material, M. Stacey, Nature, 171 (1953) 507. 

These comprise a group of organisms which, like the Gram-positive and Gram-negative groups, have been named after a staining reaction. 

Gram Stain Status Organism Shape Ulcer Location Ulcer Characteristics Ulcer Color Anterior Chamber Reaction Response to Therapy... 

Punch biopsy should be submitted in formalin to CDC. Polymerase chain reaction can also be done on formalin-fixed specimen. Gram stain and culture are frequently negative for B. anthrads after initiation of antimicrobials. 

Bacteria are classified into two groups on the basis of a staining reaction discovered by Gram in 1884. In this reaction, the cells do or do not retain a crystal violet-iodine dye complex after an alcohol wash. Cells that retain the stain are gram-positive those that do not are gramnegative. This empirical classification divides bacteria into two classes that differ in cell wall structure. 

The antibacterial properties of penicillin were discovered by Alexander Fleming in 1929. These natural penicillins produced by several species of the mold Penicillium, had a number of drawbacks. They were effective only against a type of bacteria referred to as Gram positive because of a staining reaction based on their cell wall structure. They were also very susceptible to destruction by bacterial enzymes called (l-lactamases, and some were destroyed by stomach add and had to be administered by injection. 

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