Jennifer Stearns

The way that DNA encodes the instructions for proteins is through a set of four molecules called bases, each of which represents a letter of the genetic code (A = adenine, C = cytosine, G = guanine, and T = thymine). The bases are made of carbon and nitrogen rings and are bound to a sugar and a phosphate to form a nucleotideThe nucleotides are connected together to form a long chain with the bases pointing out.

When you're studying microbiology, you need to know the key differences between the three domains of life, how scientists name and classify organisms, and how scientists identify microorganisms.Differences among bacteria, archaea, and eukaryotic microorganismsThere are three domains of life: bacteria (also known as eubacteria), archaea, and eukarya.

Prokaryotic cells come in many different shapes and sizes that you can see under a microscope. A description of the shape of a cell is called the cell morphology. The most common cell morphologies are cocci (spherical) and bacilli (rods).Coccibacillus are a mix of both, while vibrio are shaped like a comma, spirilla are shaped like a helix (a spiral, sort of like a stretched-out Slinky), and spirochetes are twisted like a screw.

Since the 19th century, there has been an explosion of great microbiological research, leading to many different branches of microbiology, all of which are both basic and applied in nature. Here’s a list of the different fields of microbiology that have developed since the discovery of microorganisms: Aquatic, soil, and agricultural microbiology study the microorganisms associated with aquatic (including wastewater treatment systems), soil, and agricultural environments, respectively.

The plasma membrane borders the cell and acts as a barrier between the inside of the cell and the outside environment. The membrane serves many important functions in prokaryotic cells, including the following: Providing sites for respiration and/or photosynthesis Transporting nutrients Maintaining energy gradients (the difference in the amount of energy between the inside of the cell and the outside of the cell) Keeping large molecules out The plasma membrane is made of a phospholipid bilayer.

Bacterial cells make a wide variety of lipids from subunits of fatty acids that have some important functions in the cell. Lipids are the main part of membranes and can be used as stores for longer-term storage of energy. Fatty acids are built by adding two carbons at a time to a growing fatty acid chain. The enzyme acyl carrier protein (ACP) is essential to this process because it holds onto the growing chain until all the carbons have been added.

Since the beginning of their widespread use in 1943, antibiotics have saved countless lives and changed the way medicine is practiced. Before their discovery, people suffered or died from infectious diseases that today are a mere annoyance, like sexually transmitted diseases and post-operative infections. Today antibiotics are essential in treating life-threatening bacterial infections, like pneumonia and sepsis, and are used preventively in a number of medical procedures (like surgery) and treatments (like cystic fibrosis).

To keep the many organisms on earth straight, in the 18th century the Swedish botanist Carl Linnaeus developed a simple nomenclature system to classify and name all organisms including bacteria. This system ranks all organisms using the following headings, shown with the example of the bacterium E. coli. Domain: Bacteria Phylum: Proteobacteria Class: Gammaproteobacteria Order: Enterobacteriales (Order names always end in –iales.