Last week I mentioned that in graduate school I studied and conducted research on cell membranes. The fluid mosaic model for the structure of cell membranes that I learned in the mid 1980s was conceived only about a decade earlier. And as I noted last week, within the last decade the view of the cell membrane has changed radically. Scientist viewed cell membranes as haphazard, disorganized systems, but now we know that the membranes are actually a careful arrangement of molecular pieces that result in exquisite organization that is integral to many functions performed by cell membranes.
As I argue in The Cell’s Design, ordering and organization of the cell membrane is one of a long list of characteristic features in biochemical systems that provide evidence for the work of a Creator.
In graduate school I focused most of my attention on the outer membrane of the gram negative bacterium Salmonella typhimurium. As a consequence, I learned quite a bit about bacteria. At that time, microbiologists viewed bacteria as simplistic “vessels” containing an assortment of life molecules randomly dispersed inside the cell. In short, microbiologists did not think that these organisms possessed any type of internal organization. This perception of bacteria stood in sharp contrast to the remarkable internal organization displayed by the complex cells (eukaryotes) that make up the multicellular fungi, plant, and animal kingdoms, as well as the single-celled protozoans.
Like the view of cell membranes, traditional understanding of prokaryotes is changing. Microbiologists now recognize that these microbes display a remarkable degree of internal organization. However, this organization doesn’t involve subcellular structures like with eukaryotic cells. Rather, the organization occurs at the molecular level—both spatially and temporally. (I detail some examples of this in The Cell’s Design.)
New work in microbiology has added to this insight. Researchers demonstrated that tmRNA, a special type of RNA molecule, displays a time-dependent spatial organization that varies through the course of the cell cycle. This biomolecule interacts with the ribosome during protein synthesis. It turns out that tmRNA organizes into a helical structure during the G1 phase and dissipates during DNA replication. The protein SmpB co-localizes and interacts with tmRNA. This organization appears to be critical and may affect how tmRNA interacts with ribosomes. This RNA molecule plays a key role in regulating protein synthesis and rescuing stalled ribosomes during the protein production process.
Common experience teaches that it takes thought and intentional effort to carefully organize a space for functional use. Instead of being a jumbled mess, the interior of the simplest cell is best described as a factory that has been carefully organized to efficiently carry out life’s most basic processes. For this reason, the surprising internal organization of bacterial cells points to the work of a Mind.
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