Microbiology: Week 2
Microbiology: Week 2 MIC 101
Popular in Intro to Microbiology
Popular in Microbiology
This 5 page Class Notes was uploaded by Marlee Delgado on Sunday October 11, 2015. The Class Notes belongs to MIC 101 at University of California - Davis taught by Eric Mann in Fall 2015. Since its upload, it has received 23 views. For similar materials see Intro to Microbiology in Microbiology at University of California - Davis.
Reviews for Microbiology: Week 2
Report this Material
What is Karma?
Karma is the currency of StudySoup.
Date Created: 10/11/15
Week 2 Microbiology Lecture I The Structure of Bacteria a The cell wall i Determines the shape and protects from osmotic lysis b Peptidoglycan i BIG polymer 1 2 sugar Derivatives a Nacetylglucosamine NAG b Nacetylmuramic Acid NAM 2 Tetrapeptide side chains a LAlanine b DGlutamic acid c Mesodiaminopimelic Acid DAP d DAlanine ii Backbone ofalternating NAM and NAG 1 Side chains attached to NAM because no one wants to hang around a nag 2 Tetrapeptide side chains on separate backbones are linked A mnrpouhvc pt39ptldimlvmn quotAu39lvllmnamn u Id l391l Awh lglucnsammv a l ALImm39 39 l lulmnr ll lllr a 39 HwUuum 39 I HJuhmuh l39thlhlm39tht lh nnl Al39l 39 3 Gram positive thick peptidoglycan layer a Contain Teichoic Acid for vertical strength b side chains linked by peptide interbridges composed of amino acids i Helps make cell wall more flexable 6mm 6 emm e a 4 Gram Negative outer membrane thin peptidoglycan layer amp periplasm a Tetrapeptide side chain are directly linked b Only to have outer membrane i Contains lipopolysaccharidesLPS c Porin proteins formed transmembrane channels d Periplasm area between outer membrane and cell membrane iii Peptidoglycan synthesis 1 Chains joined by process TRANSPEPTIDATION a Precursors have pentapeptide 5 side chains instead of tetrapeptide 4 c Capsule 1 Usually composed of polysaccharides 2 Some composed of polypeptides d Biofilms 1 Matrix outside of cell wall 2 EX Growth on a rock e Internal Structures a Cytoplasm i 80water 20 enzymes protein lipids carbohydrates b Ribosomes i 705 1 305 small unit 2 50s large unit c Nucleoid i No membrane so not nucleus ii Chromosome 1 Most Singular supercoiled double stranded iii Plasmid 1 Circular double stranded dna in cytoplasm 2 Can integrate with chromosomal DNA 3 F factorscode for conjugation 4 Rfactor code for drug resistance d Gas vesicles i Provide buoyancy for photosynthetic bacteria f Flagella g Pili and Fimbria a b c d h Spores Short hair like appendages Pili are longer Structurally similar Used to aid in attachment Can see in spore staining Resist heat UV disinfectants Spore structure a 9 Ci a Special resistant dormant structure found in some gram oplasm with normal b 39 C Bacterial Genetics a Core Gene Pool 8099 genes i Genes part of chromosome ii Homogenous GC content iii Encodes for proteins in structure and function 1 What makes a bacteria look and function like that bacteria iv 88structural genes v 10 regulatory sequences 1 Origin of replication 2 Terminus of replication 3 Promoters 4 operators b Flexible Gene Pool 0120 genes i Chunks of genes that are delivered by bacteriophage plasmids or transopons ii Different GC content iii Encode for nonessential proteins that may give the bacteria any advantage 1 Can make Ecoli friendly gut microbe harmless lab strain or pathogen strain 2 Transposable elements a Small pieces of DNA that can move from place to place b Insertion sequences i Contain gene for Transposase enzyme that inserts transopable elements c Transposons i Contain gene for transposase and at least one other gene 3 Plasmids a Small circular DNA that is independent from chromosome b Vary in size c Contain R factors d Can code for toxins e Can replicate on their own 4 Bacteriophage a Viruses that infect bacteria b Composed of genome and capsid c Replication i Attatches to bacteria and injects genome ii Bacterium is quotretooledquot to transcribe translate and replicate phage DNA iii Phage proteins assemble iv Phage lyses host bacterium 5 Transformation a Uptake of FREE DNA and incorporation into genome b Artificially done in labs i Usually involves plasmid c Natural i Can involve linear or circular DNA 6 Conjugation a Gene transfer that requires direct CELLCELL CONTACT b Outcomes i F x F F and F ii Hfr x F Hfr and F iii F x F F and F 7 Transduction a Transfer of genes from one bacterium to another via DNA bacteriophage ONLY DNA b During the process the bacterium accidently packages its own DNA into capsids 39 r I 1