AQUATIC PROKARYOTES

• Prokaryotes: without a nucleus, very small, relatively simple– Kingdom Archaebacteria– Kingdom Eubacteria

• Eukaryotes: with a nucleus, bigger, more complex– Kingdom Protista– Kingdom Fungi– Kingdom Plantae– Kingdom Animalia

MICROBES OVERVIEW

• Live in extreme environments– Less complex cell wall and

over all structure• Three main groups:

– Methanogens– Extreme Halophiles– Extreme Thermophiles

KINGDOM ARCHAEBACTERIA

• Unique form of energy metabolism– Use Carbon Dioxide and

Hydrogen to produce Methane

– Strict Anaerobes: poisoned by Oxygen

• Important decomposers (used in sewage treatment)

• Very important role living in the guts of cellulose-consuming animals– Cattle, termites, and other

herbivores

METHANOGENS

SWAMP METHANOGENS IN BIOFILM

Henry Aldrich, haldrich@micro.ifas.ufl.edu

METHANOGEN FOUND IN SANDY BIOFILM

Characteristics of a methanogenic biofilm on sand particles in a fluidized bed reactor, Lat. Am. appl. res. vol.35 no.4 Bahía Blanca Oct./Dec. 2005

METHANOGEN FOUND NEAR AN OFFSHORE OIL WELL

Complete genome sequence of Methanoplanus petrolearius type strain, Stand. Genomic Sci. 2010 3:2ISSN 1944-3277doi:10.4056/sigs.1183143

• Thrive in hot environments• Many metabolize sulfur• Maybe the most closely related

to Eukaryotes

THERMOPHILES

THERMOPHILES FOUND IN YELLOWSTONE NATIONAL PARK

http://yellowstonethermophiles.com/Forum.html Mike Bryers

THERMOPHILES FOUND IN YELLOWSTONE NATIONAL PARK

www.ryanjordan.com

THERMOPHILIC BACTERIA FROM A HYDROTHERMAL VENT

Credit: Julie Huber / Marine Biological Laboratory

TEHRMOPHILIC BACTERIAL MAT FOUND NEAR AN UNDERSEA VOLCANO 640 FEET DEEP

http://oceanexplorer.noaa.gov

• Live in salty environments• Some just tolerate salt• Some actually require an

environment 10 times saltier than saltwater

• Colonies of halophiles form a purple-red scum– Use bacteriorhodopsin

instead of chlorophyll for photosynthesis

HALOPHILES

HALOPHILES NEAR THE GREAT SALT LAKES

HALOPHILES IN OWENS LAKE, CALIFORNIA

HALOBACTERIUM SALINARIUM

Credit: NASA

• Proteobacteria– Alpha Proteobacteria– Beta Proteobacteria– Gamma Proteobacteria– Delta Proteobacteria– Epsilon Proteobacteria

• Chlamydias• Spirochetes• Cyanobacteria• Gram-Positive Bacteria

KINGDOM EUBACTERIA

• Proteobacteria: gram-negative (cell wall lacking peptidoglycan)– Named after Greek god of

the sea, Proteus (capable of assuming many shapes)

– Very diverse, taxonomy based upon rRNA (ribosomal RNA) sequences

KINGDOM EUBACTERIA

• Alpha Proteobacteria: – Most are symbiotic with a

eukaryotic host– Example: Rhizobium sp. live

in roots and ‘fix’ nitrogen gas

– Thought to be the ancestors of mitochondria in Eukaryotes

KINGDOM EUBACTERIA: PROTEOBACTERIA

ALPHA PROTEOBACTERIA

RHIZOBIUM SP. IN THE ROOT NODULES OF A PEA PLANT

http://kentsimmons.uwinnipeg.ca/16cm05/1116/16monera.htm

• Beta Proteobacteria:– Free-living and symbiotic– Key roles in chemical cycles

of ecosystems• Nitrogen cycle and

nitrosomonas sp. and Nitrobacter sp.

KINGDOM EUBACTERIA: BETA PROTEOBACTERIA

NITROBACTER SP.

Eva Spieck, Universität Hamburg

NITROSOMONAS SP.

• Purple Bacteria:– Photoautotrophs– Obligate anerobes that

extract electrons from molecules other than H2O, like H2S (producing sulfurs)• Smelly mud

– Many are flagellated

KINGDOM EUBACTERIA: ALPHA AND BETA PROTEOBACTERIA

PURPLE BACTERIA

http://www.nicerweb.com/bio1100/Locked/media/ch01/kingdom_Bacteria.html

PURPLE BACTERIA IN A SULFUR SPRING

Max Planck Institute for Marine Microbiology and Pennsylvania State University

• Some Autotrophic: obtain energy by oxidizing H2S instead of H2O, results in sulfur as a byproduct– Others are methane

oxidizers that live symbiotically in oceanic geothermal vent dwelling organisms

– Others oxidize Arsenic (maybe extraterrestrial?)

• Some Heterotrophic:– some are pathogens like

Salmonella and Klebsiella pneumoniae

– Some are normally not like Escherichia coli

KINGDOM EUBACTERIA: GAMMA PROTEOBACTERIA

KINGDOM EUBACTERIA: GAMMA PROTEOBACTERIA

University of Delaware

• Many are pathogenic to animals and are responsible for things like ulcers and blood poisoning

• Some are found near deep-sea vents where they oxidize chemicals like methane and sulfur

KINGDOM EUBACTERIA: EPSILON PROTEOBACTERIA

De Wood, Pooley, USDA, ARS, EMU

• Chlamydias: gram-negative as well– Parasites that can only live

within animal cells: Chlamydia (most common STD in the USA)

• Spirochetes: Helical in shape – Many are free-living,

Chemoheterotrophs – but many are notorious

parasites• Syphilis and Lyme disease• Distiguished by the flagella

which run lengthwise along the body

KINGDOM EUBACTERIA

• Cyanobacteria: – Known as ‘blue-green algae’– Photoautotrophs: only prokaryotes

with plantlike, oxygen-generating photosynthesis

– Their first apperence in early Earth evolution probably resulted in the atmosphere becoming oxygen-rich

– Likely ancestors of chloroplasts– Abundant wherever there is water

and provide an enormous amount of food to aquatic ecosystems

– Some species are symbiotic:– Lichen: provides the fungus

growing on trees with nutrients

KINGDOM EUBACTERIA

CYANOBACTERIA

http://cas.bellarmine.edu/tietjen/Evolution/stromatolites2.htm

CYANOBACTERIA BLOOM

Lamiot, via wikicommons

• Stromatolites: fossilized cyanobacteria colonies

CYANOBACTERIA

Paul Harrsionhttp://www.astro.wisc.edu/~townsend/static.php?ref=diploma-6

• Gram-Positive Bacteria:– Gram-positive because of

the presence of peptidoglycan in their cell walls

– Very diverse• Some are pathogens

causing tuberculosis, leprosy, anthrax, botulism, strep throat, and many more

• Most are decomposers living in soil, (by the way: partially responsible for the smell of dirt)

KINGDOM EUBACTERIA

• Decomposers: breakdown corpses, dead vegetation, and waste products, and thereby unlocking supplies of carbon, nitrogen, and other elements– Without these and other

decomposers all life would cease

• Some use CO2 to make organic compounds which is then passed up through the food chain

• Some produce atmospheric Oxygen (cyanobacteria)

• Others convert nitrogen to usable forms (nitrogen fixation and nitrification)

PROKARYOTES AND CHEMICAL RECYCLING

• Symbiosis (greek for ‘living together): ecological relationship where two organisms live in close contact with eachother– Prokaryotes often form symbiotic

relationships with others• Host and symbiont

– Mutualism: relationship where both benefit

– Commensalism: one benefits and other is not effected

– Parasitism: one eats the other but does not kill it immediately (unlike a predator)

PROKARYOTES AND ECOLOGICAL INTERACTIONS

• The well-being of many eukaryotes (including yourself) depend on the mutualistic prokaryotes– Human intestines are home to

an estimated 500-1,000 species of bacteria

– Bacterial cells in a body outnumber all human cells by as much as 10 times!

– They perform a variety of roles including breaking down foods that we can’t (plant matter especially)

PROKARYOTES AND ECOLOGICAL INTERACTIONS

• Use of E. coli in gene cloning• Bioremediation: use of organisms to

remove pollutants from soil, air, or water– Anaerobic bacteria and archaea

decompose the organic matter in sewage to be used in fertilizer

– Cleaning up oil spills– Removing radioactive material from

groundwater• Bacteria now used to make natural

biodegradable plastics (normally made from petroleum)

• Through genetic engineering, bacteria are modified to produce vitamins, antibiotics, hormones and other products

• Researchers are also engineering bacteria that can produce ethanol from various forms of biomass with the hopes of reducing fossil fuel use

PROKARYOTES IN RESEARCH AND TECHNOLOGY

GREAT SYMBIOTIC EXAMPLE: BIOLUMINESCENCE

Bill Rudman

GREAT SYMBIOTIC EXAMPLE: BIOLUMINESCENCE

http://www.ecosystm.org/squid_glowing_bacteria_work_well_together.htm

GREAT SYMBIOTIC EXAMPLE: BIOLUMINESCENCE

http://www.pbs.org/wgbh/nova/sciencenow/0305/04-glow-08.html

GREAT SYMBIOTIC EXAMPLE: BIOLUMINESCENCE

Karen Osborn of Scripps Oceanography