High G C GramPositive Bacteria

1
High GC Gram-Positive Bacteria

• By Aba Assiaw-Dufu and
• Meaghan Hollenbeck
• March 20, 2007

2
General Description

• Gram-positive typically rods
• aka Actinobacteria ? branched growth
• High guanine/cytosine content in DNA
• Pleomorphic
• Most are aerobic
• Commonly found in soil ? decompose organic
  materials
• Physiologically diverse produce antibiotics

3
Mycobacterium

• Aerobic, acid-fast, non-endospore forming,
  fungus-like growth
• Cell wall contains mycolic acids
• Contributes to pathogenicity
• Waxy layer ? survival in adverse conditions
• Found in soil, water, plants, and animals

4
Mycobacterium tuberculosis

• TUBERCULOSIS infection spread in lymph nodes and
  blood stream, most often in the lungs
• Airborne transmission
• Treated with antibiotics
• (i.e. Izoniazid and Rifampin)

5
Mycobacterium leprae

• LEPROSY chronic disease involving the skin,
  peripheral nerves, and mucosa of upper
  respiratory tract
• Transmitted through contact with nasal secretions
• Treated with antibiotics (i.e. Dapsone, Rifampin,
  and Clofazamine)

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Corynebacteria

• Catalase , club-shaped, pleomorphic, varying
  morphology with age
• Corynebacterium diphtheriae has 3 strains
  gravis, intermedius, and mitis
• Each produces an identical toxin
• Encoded on the tox gene
• Through transduction, host bacteria begins to
  produce toxin

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Corynebacterium diphtheriae

• DIPHTHERIA local inflammation in upper
  respiratory tract or toxin-mediated
  cardiac/neural disease
• Transmitted through airborne respiratory droplets
  or direct contact with infected skin lesions
• Treated with Diphtheria Antitoxin (or DAT)

8
Propionibacterium

• Slow-growing, non-spore forming, anaerobic
  bacilli
• Generally nonpathogenic
• Produce propionic acid
• Manufacture of food products (Swiss cheese ?!)

9
Propionibacterium acnes

• Causes ACNE
• Bacterium found on skin of adult humans
• Begins colonization 1-3 years before puberty
• Digestive by-products leads to an inflammatory
  response
• Treated with oral and topical antibiotics (i.e.
  benzoyl peroxide and Erthromycin)

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Gardnerella

• Difficult to assign a taxonomic position
• Facultative anaerobe, gram variable rod, highly
  pleomorphic
• Non-motile, non-encapsulated, non-flagellated,
  and non-spore forming

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Gardnerella vaginalis

• BACTERIAL VAGINOSIS vaginal flora becomes
  altered, increases pH
• Risk Factors antibiotics, douching, decrease in
  estrogen production, and increase in sexual
  partners
• Treated with Cleosin (bacteriostatic) and
  Metronidazole (aka Flagyl, bactericidal)

12
Frankia

• Aerobic, nitrogen-fixing, found in soil and
  inhabits many plants
• Membranes contain HOPANOIDS
• Stabilize the membrane
• Symbiotic relationship with several plants

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Frankia (continued)
Cause nitrogen-fixing nodules to be formed in
certain plant and tree roots
14
Streptomyces

• Resemble fungus, known best as ACTINOMYCETES,
  mostly found in soil
• Reproduce asexually by conidiophores
• Strict aerobes
• Some species produce many commercial antibiotics,
  (some have anti-cancer properties)

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Pathogenic Streptomyces

• Phytopathogens attack root vegetables
• MYCETOMA fungus tumor, usually subcutaneous, can
  sometimes invade the bone
• Treated with combination of antibiotics
• Undiagnosed or long-untreated may require
  ampuatation

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Actinomyces

• Facultative anaerobes, normally found in mouths
  and throats of humans
• Can be a part of the normal oral flora
• Opportunistic Pathogens
• Those causing disease do not exist freely in
  nature

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Actinomyces israelii

• ACTINOMYCOSIS non-contagious chronic infection
  affecting the head, neck or lungs (abscesses and
  open draining sinuses)
• Treated with high does of intravenous penicillin
  and ampicillin, followed by oral penicillin

18
Nocardia

• Filamentous aerobes, found in soil,
  morphologically resemble streptomyces
• Reproduce through fragmentation of rudimentary
  filaments fragmenting into short rods

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Nocardia asteroides

• SYSTEMATIC NOCARDIOSIS an acute, subacute, and
  chronic infection of the skin or pulmonary tract
• Transmitted through skin or pulmonary tract
• Form abscesses which can metastasize
• Treated with sulfa-based antibiotics (inhibit
  growth) and bactericidals

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Works Cited

• "Actinobacteria." Wikipedia. Wikipedia, 2007.
  Answers.com 17 Mar. 2007.
• lthttp//www.answers.com/actinobacteriagt.
• Actinomycosis. MedlinePlus Medical
  Encyclopedia. 6 March 2007. lthttp//www.nlm.nih
  .gov/medlineplus/ency/article/000599.htmTreat men
  tgt. 17 March 2007.
• American Academy of Pediatrics. Actinomycosis
  (pp.161-162) Leprosy (pp. 368-370). In
  Pickering LK, ed. 2000 Red Book Report on the
  Committee of Infectious Diseases. 25th ed. Elk
  Grove Village, IL American Academy of
  Pedicatrics 2000.
• Batra, Vandana. Tuberculosis. Emedicine. 29
  June, 2006. lthttp//www.emedicine.com/ped/topic2
  321.htmgt. 18 March, 2007.
• Bennett, Nicholas. Nocardiosis. American Academy
  of Pediatrics. June 23,2006 http//www.emedicine.
  com/ped/topic1610.htmgt March 17, 2007

21
Works Cited (cont.)

• CDC. Division of Bacterial and Mycotic Diseases.
  October 13, 2005.
• http//www.cdc.gov/ncidod/dbmd/diseaseinfo/nocar
  diosist.htm March 17,2005
• Curran, Diana. Gardnerella. Emedicine. August 1,
  2006.
• http//www.emedicine.com/med/topic841.htm.gt
  March 17, 2007
• Frankia. MicrobeWiki. MicrobWiki.kenyon.edu.
  16 August 2006. lthttp//microbewiki.kenyon.edu/in
  dex.php/Frankiagt. 17 March 2007.
• Frasseto, Lynda. Corynebacterium Infections. July
  24, 2006.
• http//www.emedicine.com/med/topic459.htm
  March 17, 2007
• Handa, Sajeev. Propiniobacterium Infections.
  Emedicine. 27 April, 2006. lthttp//www.emedicine
  .com/med/topic1917.htmgt. 18 March, 2007.
• Mycobacterium. MicrobeWiki.
  MicrobeWiki.kenyon.edu. 16 August, 2006.
  lthttp//microbewiki.kenyon.edu/index.php/Mycobacte
  riumgt. 17 March 2007.

22
Works Cited (cont.)

• Phylogeny and Protein Signatures for
  Actinobacteria (High GC Gram- Positive
  Bacteria). Bacteria (Prokaryotic) Phylogeny
  Webpage. 2006. March 2006. lthttp//www.bacteria
  l phylogeny.com/groups_ specific/actinobacteria.
  htmgt. 16 March, 2006.
• Propionibacterium. MicrobeWiki.
  MicrobeWiki.kenyon.edu. 16 August 2006.
  lthttp//microbewiki.kenyon.edu/index.php/Propionib
  acteriumgt. 17 March 2007.
• Propionibacterium acnes. 2Can Bioinformatics
  Support Portal. lthttp//www.ebi.ac.uk/2can/genome
  s/genomes.html?http//www. ebi.ac.uk/
  2can/genomes/bacteria/Propionibacterium_acnes.htm
  lgt. 17 March 2007.
• Quinonez, Jorge M. Actinomycosis. Emedicine.
  27 March, 2006. lthttp//www.emedicine.
  com/ped/topic26.htmgt. 18 March,2007.

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Works Cited (cont.)

• Smith, Scott D. Leprosy. Emedicine. 24 July,
  2006. lthttp//www.emedicine.com /med/
  topic1281.htmgt. 18 March, 2007.
• Tortora, Gerard J. Ed. Microbiology An
  Introduction. Brief Edition. The Benjamin
  Cummings Publishing Company, Inc. San Francisco,
  CA. 2005.
• Understanding Tuberculosis The Basics.
  WebMD. Reviewed by Paul Enright. 1 July,
  2005. lthttp//www.webmd.com/a-to-z- guides/unders
  tanding-tuberculosis-basicsgt. 17 March 2007