1 - Growth

Encouraged growth

Capable of removing man-made contaminants in the environment, such as oil spills, through the action of microbes that break down long chain hydrocarbons.

eg. antibiotics, bioplastics

Avoided growth

Associated with infection and disease, such as antibiotic resistance and cyanobacterial blooms.

In vitro growth

Refers to organisms grown in the lab in a controlled medium, which may not accurately represent their behavior in the wild due to the provision of all necessary nutrients for survival.

Resting state

A state of reduced activity in bacteria, some of which may produce spores for survival.

E.coli O14:H4

A strain responsible for the major 2011 E. coli outbreak, impacting mainly healthy adults through contaminated salad vegetables, causing symptoms like bloody diarrhea and kidney damage/failure.

Caulobacter

Bacteria that move towards nutrient gradients using flagella and undergo gene expression changes to adapt to different environments.

Batch culture

A closed system in which no nutrients are added or removed, allowing synchronization of cell growth.

Continuous culture

An open system where there is a continuous addition of medium balanced by the removal at the same time

One problem can be contamination

Lag phase

The initial phase in batch culture where cells adapt to new conditions and prepare for replication by synthesizing enzymes and RNA.

Log phase

A phase of rapid bacterial growth through binary fission until nutrients are depleted.

Stationary phase

A phase where nutrient limitation leads to equal numbers of dividing and dying cells, with secondary metabolism occurring.

Death/decline phase

A phase where the number of dying cells exceeds the number of living cells, leading to nutrient release and survival of spore-forming bacteria.

Peptidoglycan sacculus

A structure in the cell wall of most bacteria cells that withstands turgor pressure and requires monomeric precursors for formation.

Cell division

Must synchronize with DNA replication, involving bidirectional replication from the origin and Z ring formation.

Cell cycle in E.coli

Involves the formation of poles by the divisome during division, with old poles accumulating misfolded proteins and allowing for gene expression.

Poles / end caps

Formed by contraction on Z ring and forms a mechanism for gene expression