PPT-Gram positive bacteria

Department Nursing Second stage Lab6 Practical Microbiology I مم محمد عبدالرسول دبي AGram cocci Staphylococci and Streptococci   1 Staphylococci I General features. Gram Stain Reaction. The Gram stain reaction, named after the Danish bacteriologist Hans Christian Gram, was originally devised in 1882.. Gram staining is based on the ability of the bacterial cell wall to retain the crystal violet dye. . Last day. Brief . introduction to bacteria, . Archaebacteria. , and bacterial culturing media. . Today. We will start by looking at our cultures, and providing colony descriptors. . We . will learn about the Biology of Bacteria. Gram positive cocci. Bile-Esculin. Enterococcus. identification. Esculin. .  . Esculitin. + Glucose. esculitin. + Fe  . Ferric. citrate (. dark. . brown. ). Selective. media. Bile . added. Structure and Function. 2. Prokaryote & Eukaryote. Evolution. 3. Cellular Evolution. Current evidence indicates that . eukaryotes evolved from prokaryotes. between 1 and 1.5 billion years ago. Two theories:. Physical differences & clinical . signifigance. . . Figure 4.8b. Gram- positive bacteria. Gram-negative bacteria. Figure 4.8a. Gram-Positive cell walls. Teichoic acids:. Lipoteichoic acid links to plasma membrane. continued. Gram Stain. When bacteria are treated with a dye made up of crystal violet and iodine they react in one of two ways. . Bacteria . cells that appear purple are gram-positive and bacteria that change to pink are gram-negative. . 2. Prokaryote & Eukaryote. Evolution. 3. Cellular Evolution. Current evidence indicates that . eukaryotes evolved from prokaryotes. between 1 and 1.5 billion years ago. Two theories:. 1. . Infolding theory. Winter 2012. Ubiquity. What organisms grow best at room temperature? ___°C? . At body temperature? = ___°C?. What kind of medium is TSA? . Appearance of growth on plates. Bacteria . vs. fungi (molds)?. Lack a nucleus. DNA is naked, a single loop not bound in a chromosome. May contain plasmids (small circular fragments of DNA). Have ribosomes, but no other organelles.. DNA present as a long circular molecule.. Differentiate bacteria into two large groups (the Gram Positive and the Gram negative).. Gram status is important in medicine; the presence or absence of a cell wall will change the bacterium's susceptibility to some antibiotics. “We learn . . . 10% of what we read, 20% of what we hear, 30% of what we see, 50% of what we see and hear, 70% of what we discuss, 80% of what we experience, 95% of what we teach others.”. ~ William Glasser. Presenter: Dr. Mohammad Qadi. Introduction. Several studies evaluated resistance among . clinical. isolates in West Bank-Palestine .  . showed increasing and . alarming. rates of antimicrobial resistance . Size of a Bacterial Cell: . There are great variations in size of bacteria. . They . measure from 0.75 µ to 1.5 µ but on an average each cell of bacterium measures about 1.25 µ to 2 µ . ( . in . diameter). . Gram Positive. Gram Negative. Gram-Positive bacteria. Gram-Negative bacteria. Cell Wall. A single-layered, smooth cell wall.  A double-layered, wavy cell-wall. Cell Wall thickness. The thickness of the cell wall is 20 to 80 .