Microbiology Primer

YSU – Weapons of Mass Destruction

Historical

• Biogenesis vs. Spontaneous Generation• 19th Century – Golden Age• Germ Theory• Pasteur• Koch• Lister

Classification

• Animalia

• Plantae

• Fungi

• Protista

• Monera

Comparison

• Eucaryotic– Nuclear Membrane– Diploid DNA– Mitosis– Organelles Present– Simple Cell Wall

• Procaryotic– No Nuclear Membrane– Haploid– No Mitosis– Organelles Absent– Complex Cell Membr.

Procaryotic Organism

Bacteria

• 0.5-6 m (human hair is about 90 m)

• Simple Stapylococcus is 1.2 m

• Shape– Coccus– Bacillus– Spirillum– Spirochete

Useful Bacteria

• Acetobacter – vinegar

• Lactobacilli – yogurt, cheese

• Actinomyces – antibiotics

• Others– Industrial alcohols, acids, enzymes, rubber

and plastics

Pathogenic Bacteria

• Grp A Strep• B. pertussis• S. aureus• H. influenza• Kl. pneumoniae• L. pneumophila• M. pneumoniae• Salmonella typhi

• Plague• Cholera• Typhus• Anthrax• Q-Fever• Clostridium• Tularemia• Glanders

Bacteria

• Group Patterns

• Cell Membrane– Gram Positive– Gram Negative

Bacteria

• Endospores

• Significance– Sporulation is important in

Bacillus & Clostridium species.– Botulism disease– B. anthracis

Bacteria Reproduction

• Binary fission• Daughter cells• Population doubles each generation• Phase (important in disease)

– Lag– Exponential– Stationary– Death

Day 1 Day 3 Day 5 Day 7

Similar Organisms

• Rickettsiae– Gram negative– Difficult to stain– Grow in living cells– Treatable with antibiotics– Q-Fever– Rocky Mt. Fever

Viruses

Orthopox vaccinia

Modern antibiotics cannot “kill” viruses. In fact, questions still exist as to whether viruses are actually “alive”.

Viruses

Name that virus. . . .

Viruses

• Submicroscopic• 0.02 - 0.3 m• Either DNA or RNA• Glycoprotein

envelope• Obligate parasite

Rhinovirus 14

Viral Reproduction - RNA

• Replicates in cytoplasm

• Capsid dissolves• RNA acts as

messenger• Cell systems

harnessed for replication

Poliovirus at 350K magnification

Animal Cell

Prions

• BSE – 1986, also classified as a transmissible spongiform encephalopathies.

• vCJD

These are, in fact, incomplete shreds of protein whose origin are unknown. They can insert themselves into the genetic code of healthy cells.

Other Organisms

• Amoeba

• Flagellates Protozoans (dinoflagellates) – paralytic shellfish poisoning

• Plasmodium (malaria)

Nutritional Patterns

• Saprophytic– Live on dead organic material

• Holozoic– Ingest solid food

• Parasitic– Nutrients at expense of host

• Obligate Parasite– Requires host for specific function

Fungi

• Saprophytic

• Some produce mycotoxins

• Coccidioides imitis

• Histoplasmosis

• Crypotcoccus neoformans

Identification – Why is it difficult to monitor for bioterror

real time?• Culture

• Gram Stain

• Direct Mount

• Enzymatic Identification

• Microscopy – PCM, Bright Light, Fluorescence

• PCR

Biological Toxins

• S – Enterotoxin B

• Botulinum toxin

• Mycotoxin (Tricothecene or T2)