infections
Overview of Gram Positive Bacteria
Introduction
Gram-positive bacteria are classified by the color they turn after a chemical called Gram stain is applied to them. Gram-positive bacteria stain blue when this stain is applied to them. (Other bacteria stain red. They are called gram-negative.) Gram-positive and gram-negative bacteria stain differently because their cell walls are different. They also cause different types of infections, and different types of antibiotics are effective against them. All bacteria may be classified as one of three basic shapes: spheres (cocci), rods (bacilli), and spirals or helixes ( Bejel, Yaws, and Pinta ). Gram-positive bacteria may be cocci or bacilli. (See figure Some Gram-positive bacteria cause disease. Others normally occupy a particular site in the body, such as the skin. These bacteria, called Resident Flora , do not usually cause disease. Gram-positive bacillicause certain infections, including the following: Anthrax None Diphtheria None Erysipeloid None Listeriosis None Gram-positive coccicause certain infections, including the following: Enterococcal Infections None Pneumococcal Infections None Staphylococcus aureus Infections None Streptococcal Infections None Toxic Shock Syndrome None Gram-positive bacteria have increasingly become resistant to antibiotics. For example, Methicillin-resistant Staphylococcus aureus (MRSA) bacteria are resistant to most antibiotics that are related to penicillin. Methicillin is a type of (See also Overview of Bacteria .) 