Gram Positive

• Staphylococcus bacteria stain gram positive. Gram staining is a technique used in the laboratory that identifies the cell wall structure of a bacteria. There are two types of gram stain results: positive and negative. A positive gram stain indicates a thicker cell wall than negative stains. A gram positive stain shows up as dark blue or purple under the microscope.
  
  

Facultative Anaerobes

• The bacterium is classed by the organism's ability to culture within an oxygen-rich environment. A bacterium that grows under oxygenated conditions is called an aerobic cell. Staphylococcus are facultative anaerobes, which means they grow in the presence of oxygen but have the capability of adjusting to an environment that is devoid of oxygen.
  
  

Shape

• The shape of staphylococcus helps scientists distinguish it from streptococcus. Both of these bacteria cause disease, but they are both located on the skin and in the environment. Both are opportunistic and invade tissue in the body, so doctors are tasked with distinguishing the two types when diagnosing disease. Staphylococci are perfectly round and one micrometer in diameter.
  
  

MRSA

• Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for deadly infections in hospital settings. MRSA is an evolved strain of bacteria that acquires resistance to the common antibiotics penicillin and cephalosporins. The resistance makes the infection hard to treat with common antibiotics, so broad-spectrum antibiotics are required. These antibiotics protect against a wide range of disease-causing bacteria.
  
  

Staph Infections

• Staphylococcus is prevalent in the nose and on the skin, and normally poses no threat to human health. However, staphylococcus can be pathogenic to people with compromised immune systems, causing what are termed staph infections. Staphylococcus aureus and Staphylococcus epidermidis are responsible for the two most common types of staph infections. Staphylococcus aureus can cause boils, pimples, food poisoning, and deadly toxic shock syndrome. Staphylococcus epidermidis is a common hospital pathogen that creates a biofilm over catheters and prostheses.