Microbiology

• Bacteria with thicker walls are more resistant to antibiotics that target the cell wall.
• Peptidoglycan consists of alternating sugars (N-acetylglucosamine and N-acetyltalose) crosslinked by short polypeptide chains.
• Bacterial cells lack membrane-bound organelles such as a nucleus, mitochondria, or endoplasmic reticulum.
• Bacterial cells can have flagella, which are used for movement and can vary in number and arrangement.
• The cell wall of bacteria is primarily composed of peptidoglycan, a unique molecule not found in other organisms.
• Bacteria are single-celled prokaryotic organisms found everywhere on earth from extreme environments such as hot springs deep sea vents and acidic lakes to more familiar places like soil water air and animals
• Fungi: Eukaryotic microbes that include yeasts, molds, mushrooms, and smuts
• Protists: Eukaryotic microbes with diverse morphologies and functions
• Some bacteria have an additional layer called the capsule or slime layer outside their cell wall.
• Outer membranes contain porins, which allow small molecules like water and nutrients to pass through but prevent larger molecules from entering.
• Redi 


  1. Take jar

  2. Put decaying meat

  3. Put in environment

  4. Maggots joined and sealed the jar
• Needham, a scientist, also wanted to dispull sportorious gerente
• Needham's experiment


  1. Put and boiled broth in a jar

  2. Sealed it

  3. Became cloudy next day
• Spalazani believed Needham's experiment needed to be done differently for spontaneous generation
• Spalazani's experiment


  1. Seal jar

  2. Boil it

  3. His flask stayed clear
• Paster did an experiment that scientist Santamous believed showed spontaneous generation was not the case
• Paster's experiment


  1. Used S shaped flasks that had an arm

  2. Filled flask of broth

  3. Heated and allowed air to flow

  4. Microbes would get trapped in bud of flask
• Paster is known as the father of microbiology
• Before microbiology, it was believed that if you got a disease it was from evil spirits & curse from gods
• Fracastro thought invisible particles or seed caused disease
• Van Leeuwenhook saw what he called animalcules and actually visualized it in a hand heild scroscope
• Microscopes


  Made of carved piece of glass that the light waves will hit it and they will bend which causes magnification
• The degree of bending of the light varies depending on the microscope
• The spontaneous generation theory was about how microbes arise from non-living things
• Helmand Foral thought dirty bags+ wheat + cheese = mice
• Helmand Foral thought mice arose from non-living things
• Vancomycin binds to D-Ala-D-Ala residues on the terminal ends of pentapeptides, preventing their incorporation into new peptidoglycan strands and causing defective cell walls.
• Penicillin inhibits transpeptidation during peptidoglycan synthesis, leading to weakened or absent cell walls and eventual death of bacteria.
• The cytoplasm is surrounded by a plasma membrane composed mainly of phospholipids and proteins.
• Some bacteria may also contain plasmids, small circular pieces of extrachromosomal DNA that carry genes not essential for survival but confer advantages like resistance to antibiotics.
• Gram staining is a method used to differentiate between Gram-positive and Gram-negative bacteria based on their cell wall composition.
• Ribosomes are small structures found floating freely within the cytoplasm where protein synthesis occurs.
• Some bacteria possess pili, hairlike structures involved in attachment and transfer of genetic material.
• Prokaryotic cells do not have a true nucleus, instead having their genetic material organized into one or more loops of double-stranded DNA called chromosomes.
• Plasma membranes contain transport proteins that allow substances to enter and exit the cell.
• Some bacteria form colonies called biofilms that attach themselves to surfaces and cause problems in pipes plumbing systems and medical devices
• Most bacteria reproduce through binary fission where one bacterium divides into two daughter cells
• Yeasts: Single-celled fungi that reproduce through budding and produce alcohol when fermenting sugar
• Viruses: Nonliving particles consisting of genetic material (DNA or RNA) surrounded by protein coat called capsids
• Prions: Infectious proteins that cause diseases such as mad cow disease and Creutzfeldt-Jakob disease