Posted on 02/11/2009 8:36:55 AM PST by GodGunsGuts
Tiny Ocean Plants Offer Biochemical Enigma
by Brian Thomas, M.S.*
Phosphorus, number 15 on the periodic table of elements, is considered a basic component of all cell membranes. But the recent discovery of single-celled photosynthetic organisms surviving without the chemical element in their membranes is going to require some major rewrites to biochemistry textbooks.1
Phosphorus is in short supply in the Sargasso Sea, located in the north Atlantic, where researchers from numerous institutions and universities found several autotrophs, including some diatoms and four different genera of photosynthetic bacteria, that can make cell membrane substitutes. In their study published online in Nature, the scientists report that the bacteria substitute a sulfur molecule called sulphoquinovosyldiacylglycerol (SQDG) in place of the standard phosphorus-containing molecule.2 Not only does the bacteria’s SQDG not need phosphorus, but it doesn’t need nitrogen either! These tiny creatures still require phosphorus for their DNA, but they can get along with less of this nutrient by manufacturing their own phospholipid substitutes.
What makes phosphorus a preferred element for membrane construction? These atoms can easily provide their molecule with a negative charge. This way, the oily ends of the phospholipids automatically interlock, while the charged, phosphorus ends automatically orient toward either ocean water outside of the cell, or watery cytoplasm within the cell. The sulfonate group of SQDG, with its negative charge, is functionally similar to the phosphate groups of the phospholipids. Though not as efficient, and perhaps requiring more energy to synthesize, “sulfonic acids of this type are chemically very stable and strongly acidic.”3 Both the stability and acidic charge enable SQDG to perform its required role.
These tiny plant cells can only make this chemical substitution because they have the necessary engineering to do so. They already have all the specified machinery (enzymes), along with the ATP and UTP (energy-providing chemicals), as well as the cofactor DHAP.4 Thus, these plants are well-equipped to survive, even when times are tough. “Cyanobacteria can make membranes that require essentially no nutrients, no phosphorus and no nitrogen. Totally no nutrients at all,” stated lead author Benjamin Van Mooy.1
The new discovery challenges the standard understanding of biochemical processes. Van Mooy, of the Woods Hole Oceanographic Institute, said in a press release, “Maybe there is an underlying principle here that we will uncover.”1
Perhaps the most significant principle is that these cells’ “plan B” membranes, which require structures and information storage systems to manufacture, were not invented by any natural process. Rather, they are a backup system that the Creator planned from the beginning. The creation model predicts that more backup systems like these will be discovered.
References
1. Phytoplankton Cell Membranes Challenge Fundamentals of Biochemistry. Woods Hole Oceanographic Institution news release, February 2, 2009.
2. Van Mooy, B. A. S. et al. Phytoplankton in the ocean use non-phosphorus lipids in response to phosphorus scarcity. Nature. Published online February 1, 2009.
3. Howard, K. P. and J. H. Prestegard. 1996. Conformation of Sulfoquinovosyldiacylglycerol Bound to a Magnetically Oriented Membrane System. Biophysical Journal. 71 (5): 2573-2582.
4. Kleppinger-Sparace, K. F., and Mudd, B. J. 1990. Biosynthesis of Sulfoquinovosyldiacylglycerol in Higher Plants. Plant Physiology. 93: 256-263.
ping!
What if different, unrelated single-celled life-forms came to Earth on more than one comet?
Maybe they did - look how bizzare this new organism is. We are continually finding new and strange forms of microbial life as we explore new ecosystems. Maybe many forms of life came to Earth via comets but one core form emerged to dominate - with rest relegated to niche environments.
Is it really necessary to add to the title? What is gained by being snarky about the advancement of knowledge? Not everyone of us is so insecure in our faith that we have to take an us vs. them view of science.
They come with the territory.
If Creationists want to believe they constitute a "backup system", then they can believe that.
What they do to "evolution" is to move it out of the "gradualist doctrines of the hoary past" into a quantum present.
It should be possible to "find" preferential genes among viruses, plug them into a genome, and get a more optimally performing critter.
Kind of like putting a supercharger on your 1957 Chevy.
So scientist don’t know everything about the natural world?
Thanks for the ping!
Nothin’ snarky, other than the snarkiness of your snarkalicious whining.
Why would an omnipotent, and omniscient Creator that plans things, and can whip up a species out of nothing at anytime, need a backup system?
The fear of science is an indicator of weakness of faith. I was raised in a very religious family that encouraged curiosity and knowledge. My belief in evolutionary theory dosn’t take anything away from my faith.
How God created it isn’t nearly as importnant as my faith that he did.
Some people feel better about their faith by denigrating others.
No one here of course.
“.....is so insecure in our faith”
Those strawmen who are insecure in their faith are stupid idiots. They’re not represented in this thread, however.
Three cheers for cripplecreek.
Fear of science is an indicator of weakness of faith.
Why would a perfect system created by an infallible, all knowing God need a backup system?
Darn you.
Why do humans design adaptable/backup systems in their own designs? We are, after all, made in HIS image.
Are you saying that we are God?
I guess creationists never need grapple with enigmas, what with that handy omnipotence thing being available for all exigencies.
“the recent discovery of single-celled photosynthetic organisms surviving without the chemical element in their membranes is going to require some major rewrites to biochemistry textbooks.”
Yes, that’s how we learn about nature, it’s called science. Gaps in our knowledge exist everywhere, but they don’t mean that creationism is true by default. By this logic, even the tiniest flaw in our knowledge of human reproduction would automatically mean that babies are brought by storks.
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