This stereographic image (which can be viewed in crosseyed 3d) was created by simulating a chain of carbon atoms (similar to a protein backbone) fixed at one end and with a paintbrush at the other end. Is this system with it's output what physicists would call a "string"? This structure has program code 0.004,0,0.004,1,2,0,1,2,0,4,2,0,4,2,0.004,4,4 B17=180.0 (The numbers represent the relative rotational velocities of succesive covalent bonds, B17=180 indicates the last bond in the chain started with a 180 degree rotation). In other words, the output from a molecular program.
A single carbon atom, while possessing intriguing geometrical properties and being the basis of life as we know it, does not immediately appear very intelligent. Two carbon atoms, however, bonded together covalently, have some interesting properties. As the chain of the organic molecule grows, the more intelligent it seems to become. At the head of the molecular class, we have the networked nucleic acids and proteins of the human brain. In another sense, perhaps it should be the stem cell molecules. Evidently, given some population of molecules M at time zero, given time to evolve… at some point in time life is achieved. The transition from a dumb collection of molecules to intelligent being is a fuzzy one. When does life begin? Is it RNA molecules…or viruses? Today, bioengineers aim development of novel or improved functional molecules ("smart molecules") in areas such as the following: "Smart media" (e.g. micro emulsions, ionic liquids, mesophases) "Smart catalysts and reagents" "Smart materials and devices" (e.g. switchable and/or electro-optical materials, sensors, light-emitting diodes, solar cells)
Proteins are a class of molecules with many different biological functions and classified according to their biological roles.
. Enzymes
· Transport Proteins
· Structural Proteins
· Storage Proteins
· Hormonal Proteins
· Receptor Proteins
· Contractile Proteins
· Defensive Proteins
· Intrinsically Unstructured Proteins
. Signaling Proteins
Now we can add Computational or information processing proteins to the list. Due to their ability to transition through multiple states and accept discrete inputs, the Histone proteins are at the kernel of biological information processing.
Some examples of computational or information processing proteins include:
- Kinases: These are enzymes that can add phosphate groups to other proteins or molecules. This process, known as phosphorylation, can activate or deactivate proteins, and can serve as a way to transmit signals within a cell.
- G-protein coupled receptors (GPCRs): These are transmembrane proteins that can detect external signals and transmit them across the cell membrane to the inside of the cell. They play important roles in many physiological processes such as vision, taste, and smell.
- Transcription factors: These are proteins that can bind to specific DNA sequences and regulate the expression of genes. They can activate or repress gene expression, and play important roles in cell differentiation and development.
- Ion channels: These are transmembrane proteins that can allow ions to pass through the cell membrane. They play important roles in many physiological processes such as nerve conduction and muscle contraction.
- Ribosomes: These are molecular machines that can synthesize proteins by reading the information encoded in mRNA molecules. They can translate the genetic code into a specific sequence of amino acids to form a protein.