PPT2

• Microbial Cell Structure: Part A covers the structure and staining techniques of Gram (+) and Gram(-) bacteria.
• Part B discusses the structure-function relationship and molecule transportation in bacteria.
• Things to do in Microbial Cell Structure include understanding terms like Fluorescence-tagged antibody, TEM and SEM microscope, Lipopolysaccharide (endotoxin), O-antigen, Peptidoglycan, Peptide interbridge of peptidoglycan, Periplasm in periplasmic space, Gram stain, Archaea do not have peptidoglycan, Lysozyme, and important concepts like drawing a diagram of Gram(-) bacteria and describing the major 2 components of bacterial cell wall.
• Part A of Microbial Cell Structure discusses the structure and staining techniques of Gram (+) and Gram(-) bacteria.
• Gas vesicles are small protein compartments containing gas that provide buoyancy to a cell, enabling it to reach an ideal position in water.
• Germination is not a source of reproduction.
• Vegetative cells are produced through germination, a process that occurs after exposure to heat or chemicals.
• Storage granules are the accumulation of polymers synthesized from excess nutrient, an example is glycogen.
• Endospores are dormant cell types produced through sporulation, theoretically remaining dormant for 100 years, and are resistant to damaging conditions such as heat, desiccation, chemicals, and UV light.
• Endospores have two layers of cell wall, making them resistant to heat.
• Two common bacterial genera that produce endospores include Clostridium and Bacillus.
• One endospore yields one vegetative cell.
• Excess glucose in a cell is stored in glycogen granules.
• Part B of Microbial Cell Structure discusses the structure-function relationship and molecule transportation in bacteria.
• The Fast acid staining method is often used for staining Mycobacteria due to its ability to penetrate the cell wall.
• Many antibiotics target prokaryotic ribosomes due to their role in protein synthesis.
• The four major types of transport methods in prokaryotes are Facilitated diffusion, Group transport, Flagella and flagellin, 70S ribosome, and Plasmid.
• The structure of a prokaryotic cell includes the extracellular and intracellular spaces.
• Acid-fast Stain is used to stain members of genus Mycobacterium (TB, Hansen’s disease) and pathogenic strains in the genus Norcardia.
• Endospore stain enhances endospore staining and uses heat to facilitate staining.
• The capsule stain is an example of a negative stain (India Ink) that allows the capsule to stand out around the organism.
• Pleomorphic bacteria are able to vary shape.
• The cytoplasmic membrane defines the boundary of the cell and is a semipermeable (selectively permeable) membrane embedded with proteins.
• Gram Stain is the most widely used procedure for staining bacteria and was developed over a century ago by Dr. Hans Christian Gram.
• Proteins serve numerous functions including selective gates, sensors of environmental conditions, and fluid mosaic model: proteins drift about in lipid bilayer.
• Gram Stain can be used for presumptive identification in diagnosis of clinical specimens.
• Special Stains include Capsule, Cell body, Fluorescent dyes and tags, and Negative stain (India Ink).
• Fluorescent dyes and tags are used to observe total cells, a subset of cells, or cells with certain proteins on their surface.
• Bacteria are separated into two major groups: Gram positive (peptidoglycan) which is stained purple, and Gram negative (lipopolysaccharide) which is stained red or pink.
• Prokaryotes exhibit a variety of shapes including Coccus (spherical), Bacillus (rod or cylinder shaped), Coccobacillus (short round rod), Vibrio (curved rod), Spirillum (spiral shaped), and Spirochete (helical shape).
• Bacteria do have a cytoskeleton, though it is made up of slightly different proteins compared to eukaryotic cells.
• The light microscope can magnify 1,000x with an oil lens and is used to view bacteria, fungi, protozoa.
• The bright-field light microscope is the most common type of light microscope.
• The most critical structure in a bacterial cell is the cytoplasmic membrane.
• Cholesterol is a component of the cell membrane.
• The cell wall is a strong, rigid structure that prevents cell lysis and maintains bacterial shape.
• Plant cell wall is made of cellulose: α1,4-glucan.
• A bilayer membrane is a component of the cell membrane.
• Phospholipids and sterols are the main components of the cell membrane.
• The Archaea cell wall is not made of peptidoglycan, but rather has pseudopeptidoglycan.