Rod-like bacteria {bacillus}| include anthrax, diphtheria, typhoid, tuberculosis, and leprosy bacteria.
Bacteria {Chlamydomonas} can have two front flagella, which flex and extend to pull it through water. Flagella have ten microtubule pairs, with one pair in center. Outside nine slide along central pair. Front rhodopsin-like pigment has maximum sensitivity to blue-green light. As in rhodopsin, retinal is inside the seven membrane loops.
Bacteria {E. coli bacteria} can inhabit human intestine.
sensation
E. coli can sense sugars, amino acids, toxic ions, and light, using at least twelve different membrane and cell-wall protein receptors. They can compare previous sense qualities to subsequent sense qualities over several seconds, to establish gradients. Gradients change signal strengths by varying loop structures inside receptor proteins.
Receptors signal to G-proteins, which eventually send to six flagella. Signals combine at flagella to move bacterium in same direction or stop, which causes tumbling and random direction. Movements thus find food or escape poisons.
flagella
Flagella use hydrogen-ion gradients to turn eight ratchets at 6000 rpm. Flagella can spiral clockwise or counterclockwise. Flagella can align parallel or radiate from cell in all directions. Aligning and spiraling in same rotation causes forward motion. Radiating, and spiraling in opposite rotation, causes stopping.
Bacteria {halobacteria} (Halobacterium salinarium) can have flagella. Like rhodopsin, retinal pigment lies inside seven loops through membrane. It has maximum sensitivity to orange light, because Halobacterium lives in salt marshes.
Non-invasive gram-negative rod bacteria {pseudomonas} can cause urinary tract infections, skin infections, and other infections.
Outline of Knowledge Database Home Page
Description of Outline of Knowledge Database
Date Modified: 2022.0225