Gram-stained bacteria. Computer artwork showing gram-positive (blue) and gram-negative (red) bacteria. Gram-positive bacteria are those that are stain

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Gram-stained bacteria. Computer artwork showing gram-positive (blue) and gram-negative (red) bacteria. Gram-positive bacteria are those that are stained dark blue or violet by Gram staining, whereas gram-negative bacteria, which cannot retain the crystal violet stain, instead take up the counterstain (safranin or fuchsine) and appear red or pink. Gram-positive organisms are able to retain the crystal violet stain because of the thick peptidoglycan layer (blue, right). Because gram-negative bacteria have thin, insignificant peptidoglycan layers (red, left) they cannot retain the stain.

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Size: 4974px × 3517px
Photo credit: © HANS-ULRICH OSTERWALDER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: artwork, background, bacteria, bacterial, bacteriological, bacteriology, bacterium, biochemical, biochemistry, biological, biology, comparing, comparison, crystal, cut, cut-, cut-outs, cutout, cutouts, gram, gram-negative, gram-positive, gram-stained, illustration, layer, layers, micro-organism, micro-organisms, microbiological, microbiology, microorganism, microorganisms, negative, outs, peptidoglycan, positive, stained, staining, violet, white