Introduction & Physiology of Industrial and Environmental Microbiology

Alcoholic beverages typically utilise yeasts in their production, especially [blank_start]Saccharomyces cerevisiae[blank_end] (commonly known as baker's yeast).

Vinegar is scientifically known as [blank_start]acetic[blank_end] acid

Which of the following fungi is used in the production of citric acid?

Antibiotics are [blank_start]secondary[blank_end] metabolites synthesized by filamentous bacteria and fungi

Which type of enzyme is found in washing powders?

Which two enzymes are the main regulators of glucose breakdown?

[blank_start]Prokaryotes[blank_end] are organisms made up of cells that lack a cell nucleus or any membrane-encased organelles. [blank_start]Eukaryotes[blank_end] are organisms made up of cells that possess a membrane-bound nucleus that holds genetic material as well as membrane-bound organelles.

Prokaryote or Eukaryote? Archaea = [blank_start]Prokaryote[blank_end] Fungi = [blank_start]Eukaryote[blank_end] Protozoa = [blank_start]Eukaryote[blank_end] Algae = [blank_start]Eukaryote[blank_end] Bacteria = [blank_start]Prokaryote[blank_end]

There are 3 types of Archaea: [blank_start]Halophiles[blank_end] - Adapted to environments with high salt concentrations [blank_start]Methanogens[blank_end] - Archaea which produce methane [blank_start]Thermophiles[blank_end] - Adapted to environments with extremely high temperatures

Thermus Aquaticus gives rise to which useful genetic enzyme? [blank_start]Taq Polymerase[blank_end]

Almost all industrial bacteria are members of which two subgroups of Eubacteria?

One of the defining features of prokaryotic organisms is membrane bound organelles

The genetic material of Prokaryotes is typically found within [blank_start]a single circular chromosome of DNA[blank_end]

Prokaryotes conduct cell division via [blank_start]binary fission[blank_end] Eukaryotes conduct cell division via [blank_start]mitosis[blank_end]

Gram [blank_start]positive[blank_end] organisms have 1 cell membrane and a thick layer of peptidoglycan Gram [blank_start]negative[blank_end] organisms have 2 cell membranes and a thin layer of peptidoglycan in between

The inner membrane of a gram negative organism is also known as the [blank_start]cytoplasmic[blank_end] membrane

[blank_start]Escherichia coli[blank_end] is a gram negative bacterium which is a facultative anaerobe commonly used in the production of heterologous industrial microorganisms [blank_start]Bacillus Subtilis[blank_end] is a gram positive bacterium which is a facultative anaerobe commonly used in the production of industrial enzymes such as amylases and proteases

Eukaryotes are typically [blank_start]larger[blank_end] than prokaryotes

In eukaryotes, the nucleus is usually bound within a [blank_start]double membrane[blank_end]

The cell walls of eukaryotes consist mainly of [blank_start]cellulose[blank_end] The cell walls of fungi consist mainly of [blank_start]chitin[blank_end]

What are the two broad subgroups of Fungi? (alphabetical order, plural) [blank_start]Molds[blank_end] [blank_start]Yeasts[blank_end]

Match the subtype of Fungi to its structure: Mold - [blank_start]Filamentous Hyphae[blank_end] Yeast - [blank_start]Unicellular[blank_end]

Which of the four main classes of Fungi contain the Yeasts?

Microorganisms can be classified into two broad categories based on their energy source: [blank_start]Chemotrophs[blank_end] = Obtain energy by oxidation of organic or inorganic molecules [blank_start]Phototrophs[blank_end] = Obtains energy via light Microorganisms can also be classified into two groups based on their carbon source: [blank_start]Heterotrophs[blank_end] = Utilise a wide range of organic molecules as their carbon source [blank_start]Autotrophs[blank_end] = Utilise CO2 as their sole or primary carbon source

Most fermentation reactions are [blank_start]heterotrophic[blank_end]

[blank_start]Prototrophs[blank_end] are microorganisms that can grow on minimal media containing only carbon and energy sources and basic mineral elements [blank_start]Auxotrophs[blank_end] are microorganisms that require additional organic substances such as amino acids or vitamins

Microbial Growth Kinetics: [blank_start]Batch growth[blank_end] = Closed system whereby all nutrients are present at the start of the process. [blank_start]Fed-batch growth[blank_end] = Fresh medium is added as the reaction progresses but no old medium is removed. [blank_start]Continuous growth[blank_end] = Fresh medium is continuously fed into the fermentation vessel but used medium is removed at the same rate, creating optimum conditions for growth.

The main difference between Fed-batch and Continuous growth is that: In [blank_start]Fed batch growth[blank_end] the overall volume increases as the reaction progresses In [blank_start]Continuous growth[blank_end] the overall volume remains constant throughout the reaction

What are the four growth phases of a microorganism? [blank_start]Lag[blank_end] Phase: This initial phase is characterized by cellular activity but not growth. Cells are placed in media which allows them to synthesize proteins and other molecules necessary for replication however they do not actually divide. [blank_start]Exponential[blank_end] Phase: This is the time when the cells are dividing by binary fission and doubling in numbers after each generation time. [blank_start]Stationary[blank_end] Phase: Available nutrients become depleted and waste products start to accumulate. Bacterial cell growth reaches a plateau, or stationary phase, where the number of dividing cells equal the number of dying cells. [blank_start]Death[blank_end] Phase: As nutrients become less available and waste products increase, the number of dying cells continues to rise. The number of living cells decreases exponentially and population growth experiences a sharp decline.

In which growth phase are antibiotics typically most effective? (See description for details)

Primary metabolism produces products essential for growth and replication. This comprises the [blank_start]Lag and Exponential[blank_end] Phases and is also known as [blank_start]Trophophase[blank_end]. Secondary metabolism produces products important in ecological and other activities of the cell. This comprises the [blank_start]Stationary and Death[blank_end] Phases and is also known as [blank_start]Idiophase[blank_end].

Antibiotics are produced by the [blank_start]secondary metabolism[blank_end]

The 'Disadvantages of Batch Fermentation' slide (slide 37) seems very examinable. This could easily come up as 'Compare and contrast the different methods of fermentation' e.g. comparing batch and fed-batch to continuous. Go over and remember a few of the differences, such as: - Batch fermentation means that the system never achieves a steady state due to the constantly changing conditions of the environment. - Batch fermentation involves a lot of practical steps and procedures which gives more room for human error and contamination - Theoretically, the exponential phase in a continuous culture can be extended indefinitely as if you keep providing new material and removing old, used culture material the organism will never run out of nutrients. Click 'True' to continue.