How to identify an unknown bacterial species Factors: ·Morphology(shape) Chemical composition (often detected by staining reactions) Nutritional requirements 。 Biochemical activities Source of energy (sunlight or chemicals)
• Morphology (shape) • Chemical composition (often detected by staining reactions) • Nutritional requirements • Biochemical activities • Source of energy (sunlight or chemicals) How to identify an unknown bacterial species ? Factors:
Arrangement of Spherical Bacterial Cells diplococci streptococci tetracocci sarcinae staphylococci
Arrangement of Spherical Bacterial Cells
The Micrococcaceae The family Micrococcaceae contains gram-positive cocci,0.5-2.5 um in diameter,that divide in more than one plane to form regular or irregular clusters of cells.All are aerobic or facultatively anaerobic.The peptidoglycan di- amino acid is L-lysine. The three most important genera are: 1.Micrococcus 2.Staphylococcus 3.Streptococcus
The Micrococcaceae 1. Micrococcus 2. Staphylococcus 3. Streptococcus The family Micrococcaceae contains gram-positive cocci, 0.5-2.5 μm in diameter, that divide in more than one plane to form regular or irregular clusters of cells. All are aerobic or facultatively anaerobic. The peptidoglycan diamino acid is L-lysine. The three most important genera are:
Micrococcus-aerobic,gram-positive,catalase positive,cell arranges mainly in pairs,tetrads,or irregular clusters,nonmotile.They are often yellow, orange or red in color
Micrococcus – aerobic, gram-positive, catalase positive, cell arranges mainly in pairs, tetrads, or irregular clusters, nonmotile. They are often yellow, orange or red in color
staphylococci staphylococci Staphylococcus-facultatively anaerobic,gram- positive,usually form irregular clusters,nonmotile, catalase positive but oxidase negative,ferment glucose anaerobically
Staphylococcus - facultatively anaerobic, grampositive, usually form irregular clusters, nonmotile, catalase positive but oxidase negative, ferment glucose anaerobically. staphylococci staphylococci