Bio 215 Core Concepts by

Cultures

sandramilligan — 2025-01-02 22:37:29 UTC

eDNA analysis shows that very few organisms in any one ecosystem can be cultured in a lab

Microscopy

sandramilligan — 2025-01-02 22:38:28 UTC

Leeuwenhoek (1600s) did not share his method of making lenses so very little microscopy was done for almost 100 years after his death

Flagella

sandramilligan — 2025-01-02 22:39:27 UTC

Pseudomonas aeruginosa turns off genes for flagella production once it is embedded in a mucus biofilm (Ch 3)

ETC

sandramilligan — 2025-01-02 22:40:38 UTC

E. coli uses different ETC proteins depending on the oxygen availability. When oxygen is high, they use an ETC with low oxygen affinity that makes more ATP and when it is low, they use an ETC with high oxygen affinity to take advantage of low supplies, but only make half as much ATP. (Ch 11)

N cycling

sandramilligan — 2025-01-02 22:44:40 UTC

Ammonia oxidizing bacteria produce nitrite that is used by nitrite oxidizing bacteria (Ch 11)

Aerobic/Anaerobic Respiration

sandramilligan — 2025-01-02 22:46:32 UTC

Sulfobus switches between O₂ and other e^- acceptors depending on environment (Ch 11)

Bacteriophages

sandramilligan — 2025-01-02 22:48:17 UTC

have been studied in Russia for their therapeutic value since 1950s, but Americans rejected and ignored that work during the Cold War

Microbiome

sandramilligan — 2025-01-02 22:50:12 UTC

Human gut epithelial cells produce sugars (fucose) that support healthy organisms in the colon and the gut microbiome produces short chain fatty acids that are absorbed and metabolized in the liver for energy

Biopiracy

sandramilligan — 2025-01-02 23:14:51 UTC

Biopiracy refers to use of Native Plants and traditional knowledge of their medicinal effects by pharmaceutical companies for gain; bioprospecting is a "gentler" term for this act. Issues include lack of compensation for use of the traditional knowledge and lack of availability of the plants due to over-harvesting. Relevant to this course are antimicrobial chemicals like fungal extracts. (Ch 9)

(1992 Convention on Biological Diversity) https://www.uottawa.ca/en/news-all/biopiracy-issue-involving-dior-settled-thanks-uottawa-law-professor

Protein Structure

sandramilligan — 2025-01-02 23:26:20 UTC

Proteins in hyperthermophiles are modified to withstand high temperatures by having more hydrophobic residues, which repel water that could otherwise disrupt weak bonds and denature proteins when molecular speed increases with higher temperatures

Methanogenesis from waste

2025-03-19 16:00:03 UTC

Methanogens produces methane from carbon dioxide or more reduced forms of C, acetate. Why? These carbon sources + H₂ (energy and electrons) from other organisms allow them to live where no others can (syntrophy) Ch 19

Thermophilic

2025-03-19 16:04:48 UTC

Challenge: increased molecular movement, especially of water, which disrupts weak bonds in membranes, proteins and DNA

Adaptation: Membranes with C₄₀ tetraethers, with pentacyclic rings

Ch 19

Methanotrophs

2025-03-19 16:07:37 UTC

Use methane from methanogens as an electron donor (syntrophy)

Provide electrons to proteobacteria via nanowires (syntrophy)

Ch 19

Halophilic

2025-03-19 16:36:03 UTC

These organisms maintain the SAME osmolarity of the outside environment to reduce osmotic stress. That means HIGH osmolarity using either salts (Salt-IN approach) or compatible solutes like proline, choline, etc (Salt OUT approach).

Ch 7 and 19

# of prokaryotic species = ???

2025-03-19 16:38:57 UTC

Current estimates, based on eDNA, suggests that we can culture 1 organism for every 10⁶- 10⁹

Saccharolobus

2025-03-19 16:49:11 UTC

Chemoorganotroph with aerobic respiration when organics and oxygen are available.

Chemolithotrophy with anaerobic respiration using sulfur compounds and H₂when they have to. Ch 19

Sulphur Berries

2025-12-23 21:45:22 UTC

From AI: The bacteria within the tiny pink microbial communities ("berries") work together to form a localized, internal sulfur cycle.

The sulfate-reducing bacteria (PB-SRB1) produce sulfide.
The purple sulfur bacteria (PB-PSB1) use this sulfide for photosynthesis, converting it back into elemental sulfur, which is stored as intracellular globules.
This interspecies transfer of sulfur metabolites allows the PSB to maintain photosynthetic activity even when external sulfide levels are low.