This gene controls the operator gene in cooperation with a chemical substance called inducer present in the cytoplasm. A regulator gene is not necessarily adjacent to the operator gene which it controls. The regulator gene codes for and produces a protein called repressor.
The Gram-positive bacteria include staphylococci (staph), streptococci (strep), pneumococci, and the bacterium responsible for diphtheria (Cornynebacterium diphtheriae) and anthrax (Bacillus anthracis). The Danish bacteriologist J.M.C. Gram (1853-1938) devised a method of staining bacteria using a dye called crystal (gentian) violet. Gram's method helps distinguish between different types of bacteria. The gram-staining characteristics of bacteria are denoted as positive or negative, depending upon whether the bacteria take up and retain the crystal violet stain or not.
Gram-positive. Definition. adjective. Of, or relating to that group of bacteria that retain the violet stain following Gram's method. Supplement. The term gram-positive is used to link to a group of bacteria that retains the violet colour stain through Gram's method.Bacteria that retain the colour violet after gram staining are referred to as gram-positive in contrast to those that stain pink. The latter group is described as gram-negative.upplement. The term gram-positive is used to link to a group of bacteria that retains the violet colour stain through Gram's method. Bacteria that retain the colour violet after gram staining are referred to as gram-positive in contrast to those that stain pink. The latter group is described as gram-negative.