What is the colony morphology of Staphylococcus?
MICROSCOPIC APPEARANCE
Gram Stain: | Positive. |
---|---|
Morphology: | Spherical cocci; often forming regular and “grape-like” clusters. They occur singly, in pairs, tetrads, and short chains. |
Size: | 0.5 by 1.5 micrometers. |
Motility: | Non-motile. |
Capsules: | Usually encapsulated, however, limited capsule formation has been noted on some species. |
How can you tell the difference between Staph aureus and Staph epidermidis?
Staphylococcus aureus forms a fairly large yellow colony on rich medium; S. epidermidis has a relatively small white colony. S. aureus is often hemolytic on blood agar; S.
Is Staphylococcus epidermidis Gram negative or positive?
Gram-positive Staphylococcus
Staphylococcus epidermidis which is known as a coagulase-negative and Gram-positive Staphylococcus, is one of the five significant microorganisms that are located on human skin and mucosal surfaces with the ability of causing nosocomial infections due to the wide usage of medical implants and devices, hence until 1980 …
What is significant about Staphylococcus epidermidis?
S. epidermidis is currently the main pathogen in catheter-related bloodstream infections and early-onset neonatal sepsis and is also a frequent cause of prosthetic joint infections, prosthetic valve endocarditis, and other biomedical device-related infections (12,–15).
What properties of S. aureus distinguish from S. epidermidis?
aureus are coagulase positive, Staphylococcus epidermidis (as well as S. hominis, S. saprophyticus, and others) are coagulase negative. This is the initial result that can make this important clinical distinction.
What media is used to identify Staphylococcus epidermidis?
Tryptic soy broth (TSB) and BHI are the preferred media to grow cultures of Staphylococci. Cultures are grown at 37°C with aeration.
What are colony characteristics of Staphylococcus aureus on nutrient agar?
S. aureus – individual colonies on agar are round, convex, and 1-4 mm in diameter with a sharp border. On blood agar plates, colonies of Staphylococcus aureus are frequently surrounded by zones of clear beta-hemolysis.
What are colony morphology margins?
Characteristics of a colony such as shape, edge, elevation, color and texture….Colony Morphology.
Shape | Margin (edges) | Elevation |
---|---|---|
Circular | Entire (Smooth) | Flat |
Irregular | Undulate (Wavy) | Convex |
Punctiform (tiny) | Rhizoid | Umbonate |
Lobate | Raised |
What type of pathogen is Staphylococcus epidermidis?
Gram-positive bacterium
Staphylococcus epidermidis is a Gram-positive bacterium, and one of over 40 species belonging to the genus Staphylococcus. It is part of the normal human flora, typically the skin flora, and less commonly the mucosal flora and also found in marine sponges. It is a facultative anaerobic bacteria.