1. Lesson 9.1: Marine Viruses & Bacteria
*Refer to Chapter 5 in your Textbook

2. Learning Goals: I can explain the characteristics of a virus.
I can label & describe the structure of a bacteria.
I can differentiate between the different types of bacteria.

3. Microbes: Microbes: are organisms that are invisible to the naked eye
Types of Marine Microbes:
Viruses
Bacteria
Plankton
(Plant & Animal)

4. Marine Viruses:
A virus is a Pathogen: infectious agents causing disease and death
Only Non- living Microbe!
Rely entirely on the host for energy and use of organelles
A new field of study in marine science (~1970’s)
Infect every group of living organisms
Some are host specific (only infect a specific species)

5. Marine Viruses: General Body Structure: Occur in 3 shapes:
Head: capsid protein shell
surrounding the DNA
Tail: (some): for movement
Occur in 3 shapes:
Icosahedral- 20 faces
Helical- spiral
Binal- no shape

6. Helical
Icosahedral
Binal

7. Marine Viruses: Virus Life Cycle: Attach to a host Enter the host
Hijack host for energy
Reproduce within host
Release offspring from
the host

8. Virus Example: Fibropapilloma in Sea Turtles
Tumors made of fibrous tissue on the skin
Caused by a herpes type virus

9. Marine Bacteria: Kingdoms Eubacteria & Archaebacteria
Reproduce asexually through
binary fission to make an exact
copy
3 shapes:
Bacillus (rod)
Coccus (spherical)
Spirillum (corkscrew)

10. Marine Bacteria: Bacteria Structure: Cell wall: protection
Plasma Membrane: regulates transportation in/out
Nucleoid: single strand of DNA
Cytoplasm: gelatinous site for growth & reproduction
Flagellum: tail for movement
Ribosomes: produces proteins
Pili: used to attach to other surfaces, and exchange information with other cells (communicate)

12. Types of Marine Bacteria:
Photosynthetic Bacteria:
The most common type of bacteria is Cyanobacteria (blue-green)
Produce free oxygen as a result of photosynthesis
Exist as isolated cells or form
colonies of dense mats

13. Types of Marine Bacteria:
Photosynthetic Bacteria:
Stromatolites: a coral-like mound of bacteria that trap sediment and minerals
Only top layer is bacteria
Bottom layer is sediment

14. Types of Marine Bacteria:
Chemosynthetic Bacteria:
Use chemosynthesis to obtain energy
Found in hydrothermal vent communities
Example:
“Sulfur pearl of Namibia” Thiomargarita namibiensis
Largest bacterium in the ocean
(750 μm)

15. Types of Marine Bacteria:
Heterotrophic Bacteria:
Decomposers that obtain their energy from decaying organic matter
Important because they return inorganic chemicals to the environment

16. Types of Marine Bacteria:
Symbiotic Bacteria: “Living together” bacteria that lives inside another organism
Bioluminescent bacteria: emit light using chemical energy
Example: several species of squid have luminescent bacteria in a gland within their
ink sac, producing a luminous
cloud that might startle or
temporarily blind predators