Notes From Complexity Explorer origins of life online course summer 2020
2.3 cuatro cienegas
https://www.complexityexplorer.org/courses/155-origins-of-life-summer-2022/segments/15359
Valeria Souza et. al. 2018 "The lost world of Cuatro Ciénegas Basin, a relictual bacterial niche in a desert oasis"
https://complexityexplorer.s3.amazonaws.com/supplemental_materials/2.3+Likely+Environments+for+Studying+OoL/elife-38278-v2.pdf
mexico
Dr Valeria Souza universitad national autonoma de mexico
amazing geology
Sierra San Marcos y Pinos
marine sediments stored conditions of ancient sea
magma rich in sulfur back to archaean?
very poor in P, skewed stoichiometry
life needs 60N /P
here it's 100-200N/P
so this life needs to steal P
stromatolites and microbial mats, go back to archaen and precambrian boundary EDIACARA
Maria Kalambokidas
at Pozas Azules
archean domes microbial mat
methanogens cfreated a bubble that burst
mats hidden below salt crust
she looing at evol resilance of microbial mats
layers: methanogens make food for
then sulfur oxidizing bacts
then photosynth
WAIT SO I DON'T UNDERSTAND HOW OLD THESE COMMUNITIES ARE. ARE THEY LOOKING AT LIVING COMMUNITIES FOSSILS WHAT?
LOW IN PHOSPHORUS
3) why so many species?
looking for microbial mats and stromatolites
at ccb perhaps we have ancient lineages
the magma below recycles fluids in deep aquifer and mimics ancient ocean environments perhaps
unbalanced stoichiometry of Mg and S replicate marine osmolarity, despite being low in NaCl!
something about isotope analysis saying this composition is ancient. Wolaver et al 2013
also unbalanced stoichiometry between N and P Elser et al 2006
redfield ratio for open ocean and phytoplankton averages strongly around 16:1 individual species go from 60:1 to 6:1
in ocean this has to do with residence times and mixing. in organisms maybe it's the ratio of proteins to rRNA
ccb has much lower P ratios. these niche variables, P, S might be responsible for unique microbial communities surviving here for 100s millions of years. Torsvik 2003 stable geology: this site on the coasts of Laurentia for a long time. then 35mya the Sierras uplifted and isolated ccb from the Western Seaway Souza 2006. and the acidification of /Chihuahuan desert in the last 7my
oh they are saying this is an isolated relict from seas! even the viral part of community maintain marine signature!
N:P ratio in sediment of Churince hydrologial system is 167:1 wow. some ccb bacilii have N:P as high as 965:1
[ok whats the histogram of P usage in bacillus? phospholipids, DNA, mRNA, tRNA, rRNA, ATP, phosphorylated proteins, phosphorylated metabolites...
Alcaraz 2008 says phospholipids can be ~30% total phosphate in living organisms.
some ccb Bacillus spp synthesis sulfolipids! ability they got a long time ago by HGT from cyanos! Alcaraz 2008
https://en.wikipedia.org/wiki/Sulfolipid it's sulfoquinovosyl diacylglycerol the usual triacylglycerol with sugar head like cerebroside and a SO3- substitution
so they claim these conditions characterstic of precambrian ocean, but then abruptly in phanerozoic 542my afer glaciation continental weathering dissolved phosphates in ocean. planavsky 2010. some suggestions that cyanos and Bacilli from ccb diverged in late precambrian
Churince is closed hydrological system and most endangered site in ccb,
they find ancient ediacara endemic claids in soils but more recent jurassic invaders in aquatics
patagonia also has isolated lakes aguayo 2017
ccb also extremely diverse 57/86 known bact phyla only comparable t pearle river in china 2400km of multiple inputs. but ccb TINY 1kmm!
[[CONFUSED THEY SAY **SOIL POPS ENDEMIC BUT TALK ABOUT ANCIENT **MARINE SIGNAL]]
NOT LOT EXTINCTION EVENTS
lots of paper not make sense
the area is endangered last 50yrs
another paper tries to look at rRNA operon copy number to link to phosphorus metabolism and finds conflicting patterns
ccb is most diverse site in NA???? which is odd considering low productivity. hmm
similarities in viral sequences with gulf of mexico and sargasso sea which haven't been in contact for 35my
many strains metabolicly interdependent!
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next: Gabriela Olmedo-Alvarez Cinvestav mexico with Valeria Souza
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maybe lack of nutrients is key to diversity because low productivity makes PATCHY ENVIRON
low nutrients keep euks and multicells from competing with the bacts?
in water are stromatolites and a few 100m away there are salt crusts with interesting microbial eco
seems to be thick grassy vegetation around her poza
Souza:
then pozas rojas water from below, not rain, fluctuating environs sometimes evaporate and salinity goes up. and colors become deeper.
they are deep red!
each poza is like an island. high diversity. and a lagoon.
then in 2010 a hurricane spread the lagoon to all the pozas and enriched them with P
and fish came in during the Holocene?
well? just how stable HAS the place been?
around the pozas is scrub and bare patches
[[ARE THEY GOING TO DRILL DOWN TO DEEP AQUIFER AND SEE WHAT LIVES IN IT?]]
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Jorge Valdivia
U Nat autonoma de Mex
r operon work
ok now a poza azul, and big stromatolite shelf
why they say ediacara turned oceans BLUE?
and elsewhere are archaean domes mimicing early anoxic environments
nice layered black mud!
[I DONT UNDERSTAND HOW ANCIENT THE AQUIFER CAN BE]
