Bacterial Development and Metabolism

• Bacterial development and metabolism involves chemical components, environmental factors, nutrient requirements, and taxonomic classification.

Bacterial Chemical Components

• Water is present in free and compound forms.
• Inorganic salts include phosphorus, potassium, magnesium, calcium, and nitrium.
• Protein content ranges from 50% to 80% of dry weight, varying by bacterial species and age.
• Sugar is mainly located in the cell wall and capsule.
• Lipids are composed of lipid, fatty acid, wax, and related substances.
• Nucleic acids include RNA and DNA.

Environmental Factors Affecting Bacterial Growth

• Nutrients
• Temperature
• Hydrogen ion concentration (pH)
• Oxygen requirement

Nutrient Requirements of Bacterial Growth

• Water is essential.
• A carbon source is required.
• A nitrogen source is necessary.
• Minerals are needed.
• Growth factors are compounds a cell must have for growth but cannot synthesize and include amino acids, purines, pyrimidines, and vitamins.

Carbon Source

• All bacteria need carbon to grow.
• Bacteria are classified based on their carbon source into autotrophs and heterotrophs.
• Autotrophs are typically non-pathogenic and use CO2 as their carbon source.
  • Energy for metabolism can be obtained from sunlight and inorganic compounds.
• Heterotrophs are generally pathogenic and do not use CO2 as their carbon source.
  • Energy is obtained from complex organic compounds, such as sugar.

Temperature

• Psychrophilic forms thrive in temperatures of 15-20°C.
• Mesophilic forms, which include human pathogens and opportunistic bacteria, prefer temperatures between 30-37°C.
• Thermophilic forms grow best in temperatures of 50-60°C.

pH

• Neutrophiles grow best at a neutral pH (pH=7) and thrive in a pH range of 5 to 8; most medically important bacteria are neutrophiles.
• Acidophiles grow best at acidic pH levels below 5.5; Lactobacilli are an example of acidophiles.
• Alkaliphiles grow best at alkaline pH levels above 8.5; Vibrio cholerae grows at a pH of 8.6.

Bacterial Growth

• Bacteria multiply through binary fission.
• Generation time refers to the time it takes for a bacterial population to double.
  • Many common bacteria have a generation time of 20-60 minutes in vitro.
  • Some bacteria, like M.tb, have a generation time of 12-24 hours in vitro.
  • Most common pathogens in the body have a generation time of 5-10 hours.
• Phenomena of bacterial growth presented in liquid medium shows growth as turbidity.
• Phenomena of bacterial growth is also seen on plates.
• Motility test can be performed on semisolid medium, the test will differentiate Non mitile and motile.

Purposes of Bacterial Artificial Cultivation

• Isolating bacterial species for diagnostic and treatment purposes.
• Synthesizing essential products.
• Conducting research/study.

Bacterial Taxonomic Classification

• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species
• The Binomial System of Taxonomic Classification uses only the genus and species names.

Source of Infection

• The source of infection can be a patient, carrier, diseased animal, or animal carrier.
• Most normal flora can cause infection under abnormal conditions.

Transmission

• Transmission can occur through airborne droplets.
• Food
• Water
• Sexual contact

Explore bacterial development and metabolism, including chemical components like water, proteins, and nucleic acids. Learn about environmental factors such as temperature and pH, as well as nutrient requirements like carbon and nitrogen sources. Understand the essentials for bacterial growth.