Microbial Physiology notes-intro

Microbial Physiology notes-intro - Microbial Physiology:...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Microbial Physiology: Introduction: 3 laws of biology The 3 laws of biology: a. All biology must follow the laws of Chemistry and Physics b. All life is cellular c. All living organisms on earth arose in an evolutionary process, accounting for their similarities, differences, and relatedness i. The Universal genetic code which itself shows signs of having evolved Natural selection: a. Although there are several factors that bring about genetic change, we now have much evidence that natural selection is the most important. It is natural selection that has largely driven the divergence of the great tree of life b. Darwin’s scorecard: i. All forms of life on earth had a common ancestor ii. Natural selection is the most important factor in promoting evolutionary change iii. Sexual selection explains some of evolution iv. Humans evolved by the same mechanism as other organisms v. The discovery of genetics, which Darwin didn’t anticipate, has allowed us to understand the genetic mechanisms underlying evolution Lecture 1: September 24, 2010 The Gospel according to LUCA ( the Last Universal Common Ancestor) 1. LUCA= Last Universal Common Ancestor 2. every piece of life is a descendent of LUCA, BUT LUCA isn’t the 1 st cell LUCA is the 1 st organism from which all modern organisms can trace their lineage to 3. Major prokaryotic groups a. Gram (-) has 2 membranes i. Cell membrane cell wall outer membrane b. Gram (+) has 1 membrane i. Cell membrane cell wall 4. There are 3 Super Kingdoms in the Tree of Life: a. Bacteria b. Archaea c. Eukarya 5. Bacteria V. Archaea: a. Bacteria and archaea are similar but distinct from one another b. They have different lipids in the membrane c. Different ribosomal structure d. Different DNA polymerase
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
6. Structure is more conserved than sequence a. Over time there are mutations in the DNA sequence, but the proteins have to remain conserved for the organism to survive so even if there is a mutation, unless it’s a mutation in a key amino acid, the its most likely not going to have an affect and the protein structure will be maintained 7. Membrane topology a. Gram (-) has 2 membranes b. Gram (+) has 1 membrane c. You cant add another layer of membrane onto a cell, because it would suffocate it, therefore the evolution of the membrane topology probably went from gram (-) gram (+) 8. Conclusion: a. LUCA isn’t NOT Archaea b. Proof: archaea are derived from bacteria, therefore there is no way that archaea could be the root c. Gram (-) bacteria are LUCA Lecture 2: September 27, 2010 Microbial ecology or whose planet is this anyway?
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 6

Microbial Physiology notes-intro - Microbial Physiology:...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online