More Complex than Previously Thought – Part X – Internal Organization of Bacteria

A recent paper finds that organization within bacteria is more complex than previously thought:

Simple visual inspection of bacteria indicated that, at least in some otherwise symmetric cells, structures such as flagella were often seen at a single pole. Because these structures are composed of proteins, it was not clear how to reconcile these observations of morphological asymmetry with the widely held view of bacteria as unstructured “bags of enzymes.” However, over the last decade, numerous GFP tagged proteins have been found at specific intracellular locations such as the poles of the cells, indicating that bacteria have a high degree of intracellular organization. Here we will explore the role of chromosomal asymmetry and the presence of “new” and “old” poles that result from the cytokinesis of rod-shaped cells in establishing bipolar and monopolar protein localization patterns. This article is intended to be illustrative, not exhaustive, so we have focused on examples drawn largely from Caulobacter crescentus and Bacillus subtilis, two bacteria that undergo dramatic morphological transformation. We will highlight how breaking monopolar symmetry is essential for the correct development of these organisms.1

1). Dworkin, J. (2009). Cellular Polarity in Prokaryotic Organisms.

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A Naturalistic Fairy Tale-Part XVI

And then did we discover that minerals did co-evolve with life.1 Not that minerals did mutate, but that biological processes did transform the interstellar grains into the thousands of minerals that we find on the Earth today. All of the elements did exist in that early primordial dust, but praise Science that life did transform it into the minerals that are abundant on the Earth today. Plate tectonics did contribute, but it was the origin of life that did truly produce the diversity of minerals on the Earth today. Perhaps 2/3 of the 4300 mineral “species” that do exist on Earth today are the result of biology. Other planets, may have only 500 mineral “species.” But thanks to biology and a lot of time, we have a lot of minerals (praise Science).

1 http://www.sciencedaily.com/releases/2008/11/081113181035.htm

Digital Coding in DNA

One way of thinking about DNA is it’s information storage ability. DNA has an information storage capacity that is far beyond anything devised by humans for the amount of space that is used (information storage density). The information stored in DNA is essentially digital in nature. With computer technology, information is stored as a series of 0’s and 1’s. With DNA, the information is stored as a series of 4 different types of base molecules. All information needed for the construction of a biological organism is contained in DNA. But DNA does nothing on it’s own. Imagine taking your hard drive out of your computer. It’s useless. The same with DNA removed from a cell. There are many more functional components of a cell that are required to read the information, construct proteins from information contained in DNA, power generation, and so forth. Cells also contain error correction processes for reading DNA, just as computer technology contains processes for error correction.

Utterly, any analogy that we might try to utilize to explain the complexity of what happens in a living cell will fail. We have designed nothing of that comes close to the sophistication of a living cell. All of these functions on a cellular level are carried out with no intelligence actively guiding the process. However, all of these functions exhibit what I would call hallmarks of intelligent processes. In other words, intelligence is exhibited in the design and function of life. Life at any level of analysis exhibits something akin to intelligence. Their is an increasing trend in biology toward discovering ever increasing complexity at a cellular level. I happen to believe the miraculous is possible, but the miracle required for life to self-organize from non-living matter to living matter is beyond the level to which I can extend my faith.

Front-loading and genetics

Dave Scott over at Uncommon Descent thinks this paper has some interesting implications for ID.

As I read through, I found a few interesting tidbits.

(a) the Universal Genome that encodes all major developmental programs essential for various phyla of Metazoa emerged in a unicellular or a primitive multicellular organism shortly before the Cambrian period; (b) The Metazoan phyla, all having similar genomes, are nonetheless so distinct because they utilize specific combinations of developmental programs.

So, a couple of things that they found were:

While the presence of the opsins could be explained by their possible function in a simple light sensing, sea urchin has the entire set of orthologs of major genes involved in the eye development, e.g., Pax6, Six3, Prox1, Rx2 or Eya1 (NCBI database). Therefore, it appears that information on the eye development is encoded in the sea urchin genome, while no eye is actually developed, and thus the genetic information seems to be excessive.

….and

Also, sea urchin has Rag1 and Rag2 genes that mediate the somatic rearrangement process common to both immunoglobulin and T cell‑antigen receptor gene families. In addition, other components that function in the reorganization and diversification of immunoglobulins and TCR have also been identified, including a polymerase homologous to the terminal deoxynucleotidyl transferase (TdT) and polymerase m.11 Yet, sea urchin does not have antibodies, and possibly lacks adaptive immunity in general. Genes that are seemingly useless in sea urchin but are very useful in higher taxons exemplify excessive genetic information in lower taxons.

Ref: [Cell Cycle 6:15, 1873-1877, 1 August 2007]; ©2007 Landes Bioscience