Numberlocation of flagella are distinguishing characters 1 One

Number/location of flagella are distinguishing characters 1. One flagella = monotrichous 2. Cluster at one end = lophotrichous 3. Flagella @ both ends = amphitrichous 4. Covering the cell = peritrichous

Glycocalyx • Capsule – Protects bacteria from immune cells • Slime layer – Enable attachment and aggregation of bacterial cells

Glycocalyx/Capsule/Slime layer Not on all bacterial cells but if present it’s the outermost layer. Capsule – tends to be thick, rigid and smooth. Slime layer – is thinner & less rigid, globular *Extra layer guards against desiccation *Protects the cell from phagocytosis (S. pneumoniae) *Can be used as attachment such as in tooth decay bacteria (S. mutans)

Figure 3. 5 Glycocalyces-overview Glycocalyx (capsule) Glycocalyx (slime layer)

The slime layer is associated with the formation of biofilms, which are typically found on teeth. Fig. 4. 11 Biofilm

During nutrient depleted conditions, some bacteria (vegetative cell) form into an endospore in order to survive. Fig. 4. 21 Microscopic picture of an endospore formation

• Survival Structures A. Endospores (sporogenesis) 1. Made when the environment goes “bad” 2. Endospore contains all the important parts of the cell. 3. Only made by certain bacteria (Bacillus and Clostridium) 4. Not reproduction!! No increase in #’s 5. Autoclaving is the only way to destroy spores. 121 Celsius/15 -20 lbs. per square inch/15 -20 min.

Clostridium tetani

Cell shapes • • • Coccus Rod or bacillus Curved or spiral Cell arrangements Cell size

• Cell arrangements Single – cells found by themselves. Diplo - cells in pairs. Diplococcus, Diplobacillus Strepto – cells in chains. Streptococcus, Streptobacillus Staphylo – cells in grape like clusters. Staphylococcus