- A technique to distinguish between two major bacterial groups, based on whether or not their cell wall retains the Gram stain. Gram-positive bacteria are stained dark purple, while Gram-negative bacteria are only faintly coloured. Stain retention is determined by the structure of the cell wall.
Glossary of Biotechnology for Food and Agriculture . 2015.
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Gram staining — (or Gram s method) is an empirical method of differentiating bacterial species into two large groups (Gram positive and Gram negative) based on the chemical and physical properties of their cell walls.cite book | last = Bergey | first = David H.… … Wikipedia
Gram staining — noun Grams method of distinguishing the two main groups of bacteria … Wiktionary
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