Microbio Flashcards
Chloracniophyte
Green algae endosymbiont
Nucleomorph present
4 membranes
Euglenids
Green algae endosymbiont
Lost plasma membrane
3 membranes
Excavata supergroup
Cryptomonads
Red algae endosymbiont
Nucleomorph present
4 membranes
Rhizarians
Mixotrophic algae - multiple trophic modes
Haptophytes
Red algae endosymbiont
Nucleomorph absent
4 membranes
Haptista
Dinoflagellates
Red algae endosymbiont
Nucleomorph absent
3 membranes
Lost plasma membrane
Alveolates
Stramenopiles endosymbiosis
Red algae endosymbiont
Nucleomorph absent
4 membranes
What were the three groups of archaeplastids?
Green algae
Red Algae
Glaucophytes
Glaucophytes
Archaeplastida
They retained peptidoglycan from Cyanobacteria.
Low abundance
Mostly freshwater
What was the endosymbiont that was consumed by a eukaryotic host to create archaeplastida?
Cyanobacteria
Endogenesis Hypothesis
Archaea evolve an endomembrane system and cytoskeleton.
Consume a-protobacteria
Mito-late
Membrane composition problem
Hydrogen hypothesis
Archaea somehow gained mitochondria
Endomembrane evolved from mitochondria
Mito-early
Membrane composition problem
Syntrophy hypothesis
Delta proteum bacteria engulfed archaea
Endomembrane system evolved from inner membrane
Consumed alpha-protobacteria
Mito-late
Inside-out model
Archaea engulfed alpha- protobacteria with weird arms
Rhodophytes (Red algae)
Archaeplastida
Unicellular or multicellular
Mostly marine
Tiny nuclear genomes
Economically important
Ecosystem-forming
Green algae
Archaeplastida
Multiple independent origins of multicellularity
Eumycetozoans
Amoebozoa
Slime moulds
Fungi
Opisthokonta
Metazoa
Opisthokonta
Microsporidians
Opisthokonta
Obligate intracellular parasites
No aerobic metabolism - steal ATP directly from host
Have mitosome
Choanoflagellates
Opisthokonta
Mostly marine
Bacterivore filter feeders
Unicellular or colonial
Diplomonads
Excavata
Mostly parasites
Amitochondriate - mitosome
Parabasalians
Excavata
Amitochondriate (hydrogenosomes)
Mutualists in termite guts
Oxymonads
Excavata
Amitochondriate - lost
Mutualists in insect guts
Kinetoplastids
Excavata
Many free-living
An important lineage of insect parasites
Three genera are very relevant for human health - Trypanosoma, Leishmania, Phytomonas
Diplonemids
Excavata
SAR
Three related supergroups
Stramenopiles, Aveolates, Rhizarians
Heterokont flagellation
If the flagella are of different length then it is known as heterokont.
Heterokont flagella shows both tinsel and whiplash appearance
Stramenopiles supergroup
Motile stage with heterokont flagellation.
Includes: Oomycetes, Brown algae (phaerophytes), Diatoms
Oomycetes
Fungus-like Stramenopiles.
Often pathogenic for plants
Phaeophytes (Brown Algae)
Stramenopiles
All multicellular and often large.
Diatoms
Stramenopiles
Mostly unicellular
Main photosynthetic primary ocean producers
Planktonic and benthonic
Surrounded by a two part siliceous wall - frustule
Alveolates Super group
Cilliates, Dinoflagellates, Apicomplexans
Ciliates
Alveolates
Cilia
Nuclear dimorphism - two different kinds of nuclei
Conjugation - Transfer of genetic material between cells through contact.
Low biomass, high diversity and importance
Extremely active and voracious
Dinoflagellates
Alveolates
Cause of red tides
Essential symbionts for reef-forming corals
Unique nuclear organization - dinokaryon
Some have eyes!
Apicomplexans
Alveolates
Red algae endosymbiont
Nucleomorph absent
4 membranes
Specialized for parasitism
Agent of some infectious diseases - malaria
Rhizarians supergroup
Radiolarians, foramiferans, cryptomonads
Filose and axopodial amoebae
Radiolarians
Rhizarians
Mostly marine planktonic
Complex skeletons
Foramiferans
Rhizarians
Marine and benthonic
Skeletons commonly found in the fossil record
Haptista
Haptophytes
Major blooms in cold areas.
Coccolithophorids are covered in scales.
Hemimastigophorids and Provora
Orpangs
Don’t fit in any morphological group
Molecular data has confirmed they are a sphere ate lineage.
Excavata includes:
Diplomonads
Parabasalians
Oxymonads
Kinetoplastids
Euglenids
Diplonemids
Opisthokonta includes:
Fungi
Metazoa
Microsporidians
Choanoflagellates
How do proteins get from nucleus to plastids?
Signal peptide recognized by SRP and is translated through the endomembrane.
Signal peptide is then cleaved and transit peptide is recognized by Selma then TOC and TIC before being cleaved once it enters the matrix.
Signal peptide
short sequence of amino acids at the beginning of a newly synthesized protein that directs the protein to specific locations within or outside the cell
Hydrogenosome
Membrane bound organelle similar to mitochondria whose primary function is production of ATP.
Parabasalians
Polycistronic
Multiple proteins are coded on one strand of mRNA
Shine-Dalgarno sequences
short, conserved nucleotide sequences located in the 5’ untranslated region of bacterial mRNA that initiate translation at multiple sites within a polycistronic mRNA.
Matrix
material or environment in which cells, tissues, or organelles are embedded.
Why are kelp not considered plants?
They lack true tissues and organs like roots, stems and leaves.
Plants are defined by being a monophyletic group with a common ancestor and a unique method of reproduction, specifically retaining the fertilized egg within the mother plant in a protective structure called an archegonium. In contrast, kelp (brown algae) belongs to a different lineage (Stramenopila) and reproduces by releasing eggs and sperm into the water, similar to many algae. While both plants and kelp have evolved large, complex multicellular forms independently and have different photosynthetic origins, they are fundamentally distinct groups within the tree of life, defined by their reproductive strategies and evolutionary paths.
Mitosome
Mitochondria related organelle found in some unicellular eukaryotic organisms (Diplomonads, Microsporidians, archameoba).
Associated with the biosynthesis of Fe-S clusters.
Amoebazoans
Atmitochondrate - mitosome
Included: archaemoeba, eumycetozoans
Archaea and bacteria similarities
No endomembrane system
No cytoskeleton
Operons and polycistronic DNA
Shine-dargano sequences
No 5’ cap or poly A tail or spliceosomal introns
Similarities between archaea and eukaryotes
Single cell membrane
No peptidoglycan
Histones
TATA box
Things unique to archaea
Membrane composition - Glycerol-1 phosphate head with isoprenoid tails.
Protozoa
All heterotrophic protists
Which endosymbionts have a nucleomorph present?
Chloracnophytes and cryptomonads
Which endosymbionts have 4 membranes?
Chloracnophytes, cryptomonads, haptophytes, stramenopiles, apicomplexans
Which endosymbionts have 3 membranes?
Euglenids, dinoflagellates,
Which organisms have mitosomes?
Microsporidians, diplomonads, archaemoeba
Which organisms lost their mitochondria?
Oxymonads
