Ch 41: Biotechnology and Industrial Microbiology

Which microorganisms are the main producers of antibiotics?

Streptomyces species and filamentous fungi.

What are examples of antibiotics produced by microorganisms?

Penicillin and semisynthetic penicillin.

What are biopolymers used for in industrial microbiology?

To modify flow characteristics of liquids and serve as gelling agents.

What are biosurfactants?

Surface-active substances produced by microbes.

What are some important uses of biosurfactants?

Bioremediation, oil spill dispersion, and enhancing oil recovery.

What is reverse vaccinology?

A method that analyzes a pathogen's genome to find potential vaccine targets.

What are the key characteristics of a good antigen target for vaccine development?

It is expressed during infection, found on the pathogen’s surface, present in all strains, elicits an immune response, and is essential for survival.

How does a conserved and surface-exposed antigen help in vaccine design?

It ensures broad immune recognition and effectiveness across multiple strains by triggering a strong immune response and reducing chances of immune evasion.

What is one major advantage of using reverse vaccinology?

It speeds up vaccine development by identifying promising antigens without needing to grow the pathogen.

Why is there a growing interest in biofuel production?

Due to rising energy demands and the finite nature of fossil fuels, alternative sources like biofuels are being developed.

What is the U.S. Department of Energy’s goal for biofuels by 2030?

To replace 30% of gasoline with biofuels.

How is ethanol produced using microorganisms?

By degrading plant starches (e.g., from corn) with amylases and amyloglucosidases, followed by microbial fermentation.

How is hydrogen gas produced by microbes?

As a direct product of fermentation, using enzymes like hydrogenase and nitrogenase.

Which microorganisms are commonly involved in ethanol production?

Yeast

Which microorganisms are commonly involved in hydrogen production?

Cyanobacteria and algae

What conditions must be controlled when growing microbes industrially?

Agitation, temperature, pH, and oxygenation.

What is the purpose of a continuous feed system in microbial growth?

To constantly add a critical nutrient and prevent waste buildup.

What is fermentation scale-up?

The process of increasing fermentation volume while maintaining efficiency and control over microbial growth.

When do secondary metabolites typically accumulate?

After active growth, often as part of a stress response.

What types of metabolites are produced after active growth, often during stress responses?

Secondary metabolites like antibiotics, fermentation byproducts, and stress-response enzymes.

What is a common example of a secondary metabolite?

Penicillin.

What are primary metabolites?

Compounds essential for growth and reproduction, such as amino acids and nucleotides.

What are secondary metabolites?

Compounds produced after growth that help with ecological functions like defense or competition.

What is the role of Bacillus thuringiensis (Bt) in biopesticide use?

Produces a toxin that specifically targets insect larvae without harming humans or beneficial organisms.

How do microbes contribute to nanotechnology in MRI imaging?

Some bacteria produce magnetosomes—magnetic particles that can enhance contrast in MRI scans.

How can microalgae help with wastewater treatment and sustainability?

It can absorb excess nitrogen and phosphorus from wastewater and can be harvested as biomass for feedstock or biofuel.