Summary

Summary Bacterial Diversity

0 purchase

Course
Molecular And Cell Biology (MCBG2038A)

Institution
University Of The Witwatersrand (wits)

The summary includes: Information on bacterial phyla specifically looking at Actinobacteria, Bacteroidetes, Firmicutes, Deinococcus-Thermus, Proteobacteria and Spirochaetes. Identifies and differentiates between the bacterial phyla described above. Examples from each of the bacterial phyla are d...

[Show more]

Preview 2 out of 7 pages

View example

Uploaded on August 3, 2023
Number of pages 7
Written in 2021/2022
Type Summary

Institution
University of the Witwatersrand (wits)
Course
Molecular And Cell Biology (MCBG2038A)

$3.80

Add to cart

Save

100% satisfaction guarantee
Immediately available after payment
Both online and in PDF
No strings attached

Intended learning outcomes (ILOs)
• List at least four bacterial phyla
• Identify and differentiate between the bacterial phyla described here
• Discuss and explain examples from each of the bacterial phyla described here
• Discuss the impact certain bacterial species have on human health
Bacterial Phyla
Acidobacteria, Actinobacteria, Aquificae, Armatimonadetes, Bacteroidetes, Caldiserica, Chlamydiae, Chlorobi,
Chloroflexi, Chrysiogenetes, Coprothermobacterota, Cyanobacteria, Deferribacteres, Deinococcus-Thermus,
Dictyoglomi, Elusimicrobia, Fibrobacteres, Firmicutes, Fusobacteria, Gemmatimonadetes, Lentisphaerae,
Nitrospirae, Planctomycetes, Proteobacteria, Spirochaetes, Synergistetes, Tenericutes, Thermodesulfobacteria,
Thermotogae, Verrucomicrobi
Actinobacteria
→ Members of the phylum Actinobacteria are Gram-positive and known for their high guanine and cytosine
(GC) content in their DNA.
→ While they can be isolated from aquatic environments, they are the one of dominant bacterial phyla in the
soil.
→ In the soil the Actinobacteria display a filamentous morphology like that of filamentous fungi.
→ The bacteria form extensive mycelial networks that form symbiotic associations with plants – the bacterium
fixes nitrogen in exchange for plant produced sugars.

• Streptomyces
⤷ Streptomyces is the largest bacterial genus with over 500 described species.
⤷ Members of this genus are known for the complex secondary metabolism and produce more than two-
thirds of all our naturally produced antibiotics (neomycin, cypemycin, grisemycin, bottromycins and
chloramphenicol).
⤷ Interestingly, the Streptomycetes are the ones that produce that distinct "earthy" smell after rain.
⤷ The bacterium produces the volatile compound geosmin which becomes more pronounced after the
rains.

TJW Notes

, Bacteroidetes
→ The phylum Bacteroidetes is composed of Gram-negative, non-spore-forming, anaerobic or aerobic, rod-
shaped bacteria that are widely distributed in the environment
→ They ate a major member of the human gut microbiome reaching up to 1011 cells per gram of intestinal
material.
→ They perform metabolic conversions that are essential for the host, such as degradation of proteins or
complex sugar polymers.
→ They also modulate the host immune system through specific interactions.
→ Reduced abundance of the Bacteroidetes in the gut microbiome is associated with obesity.
→ However, the bacterial group appears to be enriched in patients suffering from irritable bowel syndrome
and is involved in type 1 and type 2 diabetes.
→ Bacteroides spp. are specifically were associated with adiposity, insulin resistance and an inflammatory
phenotype.

Firmicutes
→ The Firmicutes are a phylum of mostly Gram-positive bacteria that can be spherical or rod shaped.
→ In contrast to the Actinobacteria, the Firmicutes are the low-G+C group.
→ Many produce endospores, which are resistant to desiccation and can survive extreme conditions and are
therefore important human pathogens.

• Clostridium
⤷ Clostridium is a genus of Gram-positive bacteria.
⤷ They are obligate anaerobes and are rod shaped.
⤷ They are known for their characteristic bowling pin shaped endospores.
⤷ Clostridium species inhabit soils and the intestinal tract of animals,
including humans.
The main species responsible for disease in humans are:
1. Clostridium botulinum
2. Clostridium perfringens
3. Clostridium tetanus

1. Clostridium botulinum:
→ Clostridium botulinum produces the botulinum toxin which can cause botulism.
→ The toxin prevents the release of acetylcholine inhibiting muscle contraction.
→ If the respiratory muscles are targeted it can lead to respiratory failure and death.
→ Interestingly, the toxin has found application in the medical field.
→ Botox (botulinum toxin) and is commonly used in cosmetic surgery to paralyze facial muscles to
reduce the signs of aging.
→ It is also used to in the treatment of chronic migraines.
TJW Notes

The benefits of buying summaries with Stuvia:

Guaranteed quality through customer reviews

Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.

Quick and easy check-out

You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.

Focus on what matters

Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!

Frequently asked questions

What do I get when I buy this document?

You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.

Satisfaction guarantee: how does it work?

Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.

Who am I buying these notes from?

Stuvia is a marketplace, so you are not buying this document from us, but from seller tiffanyjanewilton. Stuvia facilitates payment to the seller.

Will I be stuck with a subscription?

No, you only buy these notes for $3.80. You're not tied to anything after your purchase.

Can Stuvia be trusted?

4.6 stars on Google & Trustpilot (+1000 reviews)

66184 documents were sold in the last 30 days

Founded in 2010, the go-to place to buy study notes for 15 years now

Start selling