Bacteria which stain blue in the differential stain, called the Gram stain; possess a thick cell wall with no outer membrane.

Bacteria whose cell wall is composed of a thick layer of peptidologlycan with attached teichoic acids. In the Gram-staining process, these bacteria retain the stain.

The cell wall of gram-positive bacteria, consisting of a thick layer of peptidoglycan and teichoic acids. In the course we will discuss the following low G+C gram-positive bacteria: Sreptococci and Staphylococci, and Liseriae; we will discuss the followoing high G+C gram-positive bacteria: Corynebacterium diphtheriae and Mycobacterium tuberculosis. (Lecture: The Bacterial Cell: Structure, Function, Growth, and Gene Regulation I, 1/24/02)