BAROPHILES

WHAT IS A BAROPHILE?

• Piezophiles
• Thrive under extreme high pressures
• Generally found on deep ocean floors

HABITAT & MODE OF LIVING

• Lives under pressure
• Lives under the sea in deep trenches
• Lives in extreme temperatures
• Lives in darkness (UV sensitive)
• Lives in colonies

SHAPE & SIZE

• Rod shaped (bacilli)
• Usually just found as a solitary rod
• But can be arranged in chains (streptobacilli)
• About 1-3 micrometers long and 1 micrometer wide

Cell Wall Composition

Bacteria - peptidoglycan
Gram-negative
Archaea - lipopolysaccharides

MOBILITY

• Has flagella (3 parts)
• Basal apparatus- system of rings embedded in cell wall + plasma membrane
• Hook- attatched to and is turned by the basal apparatus and filament
• Filament- chains of flagellin (a globular protein)
• Powered by ATP

HOW DO THEY OBTAIN ENERGY & CARBON

• obligate anaerobic
• hydrothermal vents on ocean floor release hydrogen sulfide and minerals
• provide energy for chemosynthesis - process by which organisms use chemical energy to produce
• carbohydrates (usually in absence of sunlight)
• uses naturally occurring carbon in oceans, provide source of carbon for benthic animals that ingest bacteria

Describe the range of differences in this aspect of prokaryotic life

DEPTH

• Depth: avg 80-500 m
• Barotolerant- up to 1220 m (4000 ft)
• Barophilic- up to 1830 m (6000 ft)
• Extrememe barophilic- up to 2135 m (7000 ft)
• xenophyophores - in the deepest ocean trench (6.6 miles/10,541 meters)

TEMPERATURE

• Thermoplezophile- lives near hydrothermal vents at up to 400 C, avg 98 C
• Psychroplezophile- not near hydrothermal vents 2-4 C

PRESSURE & Ph

• 10-110 MPa (100-1100 atm)
• avg 38 MPa
• extreme barophiles >40 MPa
• At higher pressure, the optimal growth occurs at a higher temperature
• Ph 7.6 (because it lives in water)

DO DIFFERENCES IN THIS CATEGORY DEMONSTRATE EVOLUTIONARY RELATIONSHIPS?

evolution - all barophiles:
make special enzymes/proteins that hold the cellular structure together (increased binding capacity)
surrounded by proteins for protection
protection from pressure and cold by unsaturated fatty acids in membranes

What are the other physiological & biological implications of organism falling into one category or another?

Barophiles have adaptations that other organisms do not have in order to live in its environment. For example, the high pressures experienced by these organisms can cause the normally fluid cell membrane to become waxy and relatively impermeable to nutrients. It is UV sensitive so it lives in the dark.

Explain why the biological species concept is not useful to prokaryotes

Th biological species concept defines a species by the capability to produce fertile offspring. Prokaryotes are asexual and produce by binary fission