Types of Compounds. Ionic compounds are compounds composed of ions, charged particles that form when an atom (or group of atoms, in the case of polyatomic ions) gains or loses electrons. 1  A cation is a positively charged ion. 2  An anion is a negatively charged ion.
Porins are members of an extended family of transmembrane proteins found in the outer membrane of gram negative bacteria such as E. coli, or in the outer membranes of mitochondria in eukaryotes. The general porins provide a simple diffusion pathway across the membrane for molecules less than 1 kDa with little substrate selectivity.
Globular Protein. Photo by: Sebastian Kaulitzki. In a globular protein, the amino acid chain twists and folds in a manner that enhances the protein's solubility in water by placing polar groups of atoms at the protein's surface (where they can participate in attractive interactions with water molecules).he shape assumed by a globular protein molecule tends to maximize both types of attractive forces, whereby. Figure 1. The 3-dimensional molecular structure of the globular protein polymerase Î². The ribbon represents the backbone of the amino acid chain with the various amino acids depicted by shading.