Ways microbes save the world
Ways microbes save the world pt 2
Eukarya
Endosymbiotic theory
a) aerobic heterotrophic prokaryotes engulfed to become mitochondria
• alphaproteobacteria - mitoch. ancesto
b) photosynthetic prokaryotes engulfed as plastids (chloroplast)
• occurred later after mitochondrial development
• Cyanobacteria - plastid ancestor
Evidence of symbiosis
Enzyme heavy inner plasma membrane
& transport chains (modern prokaryote)
• similar splitting to binary fission of prokaryote
• circular bodied DNA not associated w/ proteins
• tRNA, ribosomes, for protein synthesis
• move more similarity to pro than euk
Protista diversity
A) historical perspective - discovery of new organisms and development of more accurate descriptions
Was originally paraphyletic
Protist diversity cont.
B) current hypothesis
Eukaryotic tree demonstrative off process of science (root is uncertain) and shows all 4 branching at the same time
• 4 main groupings of eukaryotes
1) excavata
Similarities in cytoskeleton morphology
• most have excavated groove used for feeding
• molecular evidence supports the mono phyletic arrangements of groups working
Giardia intestinalis
EXCAVATA
Trypanosoma Spp.
EXCAVATA
The SAR clade
Photosynthetic protist, unicellular algae
• glass like silica wall
• highly diverse (100,00+ species)
• CO2 sequesterer
Diatoms (bacillariophyta)
SAR CLADE
Brown algae (phyopheta)
SAR CLADE
Dinoflagellates
ALVEOLATES of SAR CLADE
* complex lifecycle in multiple host, sexual and asexual
Plasmodium
ALVEOLATES of SAR CLADE
• common ancestor acquired a Cyanobacteria through endosymbiosis
Archeoplastida
First O2 and N producers that changed the world
Cyanobacteria