gram positive bacteria that can grow on macconkey agar
MacConkey agar By utilizing the lactose available in the medium, Lac+ bacteria such as Escherichia coli, Enterobacter and Klebsiella will produce acid, which lowers the pH of the agar below 6.8 and results in the appearance of pink colonies. The bile salts precipitate in the immediate neighbourhood of the colony, causing the medium surrounding the colony to become hazy.[4][5]
Mycobacterium leprae Mycobacterium leprae, also known as Hansenâ€™s bacillus spirilly, mostly found in warm tropical countries, is a bacterium that causes leprosy (Hansen's disease).[1] It is an intracellular, pleomorphic, acid-fast, pathogenic bacterium.[2] M. leprae is an aerobic bacillus (rod-shaped) surrounded by the characteristic waxy coating unique to mycobacteria. In size and shape, it closely resembles Mycobacterium tuberculosis. Due to its thick waxy coating, M. leprae stains with a carbol fuchsin rather than with the traditional Gram stain. The culture takes several weeks to mature.