Dwarf Workpersons in the Carbonate Factory -- an Examination of the Fantastic Roles that Nannobacteria Play in the Precipitation of Carbonate
Robert Folk (Department of Geological Sciences, Universityof Texas at Austin, Austin, Texas, USA)
14th Symposium on the Geology of the Bahamas and Other Carbonate Regions held at Gerace Research Centre, San Salvador Island, Bahamas
13 June 2008
Nannobacteria (preferred geologic spelling) vs. nanobacteria (widely used spelling).
Folk has fallen in love with Italy in recent years. In Rome, St. Peters’s is made of travertine. Then, looked at hot springs travertine. The hot water here comes out at 60° C. Hot water deposits have trigonal calcite crystals and aragonite needles.
Sulfur bacteria are in flowing hot springs - long streamers, ~1µ long and many centimeters long. These lithify quickly. Can see aragonite spherulites under the SEM.
Viterbo hot springs calcite - saw normal bacteria, ~1.5µ in size, and some mucus strands. These are normal bacteria.
Etched aragonite spherulites from Viterbo hot springs under SEM show lots of ~1/60µ balls below the aragonite needles. There are such things as nannobacteria - they are ~1/10 the size of normal bacteria.
Bacteriologists have claimed that 0.2µ is the lower limit of life. Well, there is a gradation in size below that level. 0.2µ is not a magic cutoff point.
Bacterial cell walls are negatively charged, so it attracts Ca+2 ions - bacteria get calcified.
Nannobacteria are dwarf bacteria ranging in size from 0.2µ to 0.05µ. They occur as balls, rods, chains of balls.
Under the SEM, have seen fuzzy dumbbells of aragonite needles, strands, and calcified bacterial cells.
Why is there calcite sometimes in these hot springs? Why is there aragonite sometimes in these hot springs?
It depends on the temperature of the water (>40° C - get aragonite; <40° C - get calcite) and the Mg/Ca ratio in the water (>1.0 - get aragonite, like marine water; <1.0 - get calcite).
Can see a complete transition in nannobacterial size from 0.2µ to 0.05µ, maybe even down to 30 nm (0.03µ). This is pushing the envelope for the size of life.
Entire calcite crystals can be seen to be composed entirely of little balls (= nannobacteria).
At the end of aragonite needles, nannobacterial balls can be seen.
Have seen aragonite, calcite, dolomite all forming at the same time.
Green slime from a hot spring - has aragonite fuzzy dumbbells. TEM images show matrix between dumbbells - matrix is full of biologic material (bacteria and nannobacteria). 200 nm is not the lower limit of life.
Great Salt Lake oolites (Utah) - have concentric banding - all aragonite (high Mg/Ca ratio in Great Salt Lake waters). Found nannobacteria in etched Great Salt Lake oolites. Aragonite needles in oolites - end-on views of aragonite needles are full of nannobacteria. They are doing the work of CaCO3 precipitation.
It’s not a new idea that oolites are related to organic matter, but high-magnification SEM study hasn’t been done. Geochemists traditionally think oolites are great examples of inorganic precipitation.
Bahamas oolites - they turn black when put in an oven - the organic matter maturates. Oolites have to have organic matter in the interior in order to do this.
Lots of cyanobacterial (apparently) borings occur in oolites.
Concentric banding in oolites consists of mucus band-aragonite needles-mucus band - aragonite needles, etc. This is what causes oolite concentricity. Concentricity is regular and periodic - don’t know why yet - may be a geochemical proceses.
Oolite aragonite needles are formed by nannobacteria.
Inorganic aragonite needles - have hexagonal shaped ends. Can see crystal faces & edges.
Organic aragonite needles - have elliptical shaped ends.
Viruses are a little smaller than nannobacteria.
Some of the carbonate we see may have been precipitated by viruses.
Published Persian Gulf nannoballs from the 1970s - interpreted here as nannobacteria.
Ancient limestones - Triassic Portoro Limestone of Italy - etched samples have nannobacterial-sized balls also.
This has also been seen in Ordovician limestones and Australian Proterozoic limestones.
Dolomite crystals have been formed by nannobacteria - built layer on layer like billiard balls on a table.
Negatively charged cells walls attract Ca and Mg - get dolomite.
Laguna Madre, Texas dolomite - saw nannobacterial bodies.
There are non-nannobacterial constructed carbonates (dolomite, for example).
One can tell the difference between organic and inorganic dolomite.
Unwanted calcium deposits occur in the human body - nannobacteria turn out to be the cause. Medical scientists have acknowledged the existence and validity of nannobacteria. Non-medicine biologists tend not to.
Kidney stones & cataracts with calcification - nannobacteria are doing the work.
Arterial blockages of calcium phosphate - done by nannobacteria.
Nannobacteria can catch and lithify together red blood cells.
40 nm wide - the size of Martian nannobacterial strands - they are the size of life forms.
Can see the same nannobacteria in Martian rocks as on Earth. There is extraterrestrial life.
Can see the same size range in nannobacterial balls from the Proterozoic to the modern.
Even in non-etched samples, can see nannobacteria. They are better seen in etched samples. They are not artifacts of etching.
Precipitation is a by-product of nannobacterial physiology.
Charged cell walls attract cations.
Bacteria and nannobacteria are like humans - there’s lots of them, but there are very few in the Sahara vs. tons of them in New York City. So, bacteria and nannobacteria have a patchy distribution on Earth - probably based on a patchy food distribution.
Theoretical arguments on the lower limit of life are based on unwarranted assumptions - you could have short DNA chains and very few ribosomes in a cells, despite the conclusions of an anti-nannobacteria conference in Washington D.C. in 1999.
The medical community mostly accepts the validity of nannobacteria.
Microbiologists mostly don’t accept the validity of nannobacteria yet.
Why aren’t these balls viruses? Nannobacteria can be cultured without large bacterial cells present. Viruses need other cells to reproduce. They are clearly not viruses.