Life cycle and Genotyping
from: Acanthamoeba: Biology and Pathogenesis (Author: Naveed Khan). Caister Academic Press, U.K. (2009)
Abstract
• Life cycle
Trophozoite stage
Growth phase
G1 phase
S phase
G2 phase
Mitosis (M) phase
Cell division in asynchronous cultures
Cell division in synchronous cultures
Stationary phase
• What is the best stage in Acanthamoeba cell division to induce encystation?
• Encystation
At the morphological-level
At the organelle-level
RNA and protein synthesis
Golgi complex
Phagocytic and pinocytic activity
Respiration
Cytoskeletal proteins
Lipids
Other molecular changes
Cell wall synthesis
Cyst stage
Excystation
• Regulators of life cycle
• What stimulates encystation?
Food deprivation
High cell density
Surface receptors (hyper- and hypo-osmolarity, extremes in pH)
Encystation-inducing factors
Chemical factors
• Feeding
• Metabolism
• Acanthamoeba is a heterotroph (chemo-organotroph)
Glycolysis pathway (also called Embden- Meyerhof-Parnas pathway)
Krebs cycle (also called citric acid cycle or tricarboxylic acid cycle)
Electron transport
• Isolation of Acanthamoeba from the environmental samples
Xenic cultivation (non-nutrient agar plates seeded with Gram-negative bacteria)
"Axenic" cultivation
Chemically-defined medium
• Methods of encystation
• Storage
• Determination of the viability of trophozoites and cysts
• Speciation and genotyping
Use of 18S rRNA gene sequences (18S rDNA)
