L5- Modern Age Microbio

Why did learning about microorganisms make such a big contribution to biology-related sciences?

Why use microorganisms?

• Much of what has been learned about microbes also applies to other organisms→ including humans

Use them bc

• No ethical ruling

• Rel. easy to grow

• take up little space

• available by trillions

Contribution of microbio to biology related sciences

• Biochemistry is the study of..

• Metabolism

  • =the chem rxns that occur in living organisms

Biochemistry began with

• Pasteur’s work on fermentation

• With Buchner’s discovery on enzymes in yeast extract

• In early 1900s many scientists still thought metabolic rxns of microbes had little to do w/ metabolism of plants + animals

What did microbiologists Albert Kluyver and his student van Niel propose

• That basic biochemical rxns are shared by all living things

  • primary ft of these rxns is the transfer of e-s and H+

Genetics is study of

• inheritance

• started in mid 1800s as offshoot of botany

Scientists in genetics studying Bacterium Streptococcus pneumoniae discoverred

• Oswald Avery

• Macleod

• McCarty

Determined genes are contained in molecules of DNA

By studying Mold Neurospora crassa the scientists established

• Beadle + Tatum

• Working with bread→ established that each gene codes for a specific protein, which determines its function

Esther Lederberg using different microbes determined

• exact way in which genetic info is translated

• Rates + mech of genetic mutation

• methods by which cells + viruses control genetic expression

Molecular biology combines aspects of

• biochem, cell bio, and genetics to explain cell fx at the molecular level

• Molecular biologists concerned partic. w/ genome sequencing

Carl Woese and George Fox discovered

• that significant differences in nucleic acid seqs among organisms clearly reveal that cells belong to 1 of 3 major groups

  • not just 2 groups like they though

• bacteria

• Archaea

• Euks

Banfield used gene sequencing data to analyze and understand

• microbes that haven’t been grown in labs

Recombinant DNA tech

• commonly called genetic engineering

• First developed using microbial models

• Geneticists manipulate genes in microbes, plants, and animals for practical applications

• ex) E.coli most commonly used→ hemophiliacs

What does recombinant DNA tech for gene therapy involve

• inserting a missing gene

• repairing a defective one in human cells

ex) researchers insert a desired gene into host cells, where it’s incorporated into a chromosome + begins to fx normally

What process is used for microbes in communities to transmit information among themselves

• quorum sensing

Microbial communities can be used for

• Pathogenesis→ causing human and animal diseases

• Pharmaceuticals→ production of vitamins

• Bioremediation→ use of living bacteria, fungi, and algae to detoxify polluted envts

• Biodegradation→ decay of dead organisms + recycling of chemicals such as C, N, S

What scientists developed lab techniques for important aspects of envt microbiology

• Beijerinck + Winogradsky

Questions that drive microbiological investigations today

• How can we develop successful programs to control/eradicate diseases like TB, malaria, AIDS, and ebola

• Can bacteria and archaea be used in ultraminiature technologies like living computer circuit boards

• How can an understanding of microbial biofilms help us understand aspects of microbial action in preventing and curing diseases

• How can we reduce threat from microbes resistant to antibitoics