Презентация на тему Halobacterium salinarum

organism from the halophilic branch of Archaea
It is

classified as an extremophile due to its ability to survive in environments with very high salt concentrations.
Due to their high salinity, these salterns become purple or reddish color with the presence of halophilic Archaea.

Class: Halobacteria
Order: Halobacteriales
Family: Halobacteriaceae
Genus: Halobacterium
Species:

H. salinarium

a highly concentrated salt solution (mainly consisting of potassium

chloride, KCl)
This commitment to an extremely salty existence has its advantages; H. salinarum can grow with less interspecies competition than microbes living in more moderate conditions such as the ocean.

energy for H. salinarum, particularly arginine and aspartate, though

they are able to metabolize other amino acids, as well.[2] H. salinarum have been reported to not be able to grow on sugars, and therefore need to encode enzymes capable of performing gluconeogenesis to create sugars. Although "H. salinarum" is unable to catabolize glucose, the transcription factor TrmB has been proven to regulate the gluconeogenic production of sugars found on the S-layer glycoprotein.

simple salts medium with lactate, pyruvate, glucose, or glycerol

as sole carbon sources.

cultivated in bacteriological peptone, tryptone and yeast extract medium.

in bacteriological peptone, tryptone and yeast extract medium.

in bacteriological peptone, tryptone and yeast extract medium.

in full-tryptone medium of a shaker flask and half-tryptone

medium of a bubble column photobioreator, black-solid and red-broken arrow indicates full and half tryptone medium replacement.

half-tryptone medium in a bubble column photobioreator under repeated

batch operation. (pH 7,2)

in fulltryptone medium of a shaker flask and half-tryptone

medium in a bubble column photobioreator under repeated batch operation.

polyploid and highly resistant to ionizing radiation and desiccation,

conditions that induce DNA double-strand breaks. Although chromosomes are initially shattered into many fragments, complete chromosomes are regenerated by making use of over-lapping fragments. Regeneration occurs by a process involving DNA single-stranded binding protein, and is likely a form of homologous recombinational repair.

of H. salinarum, NRC-1[2] and R1.[20] The Halobacterium sp.

NRC-1 genome consists of 2,571,010 base pairs on one large chromosome and two mini-chromosomes. The genome encodes 2,360 predicted proteins.[2] The large chromosome is very G-C rich (68%).[21] High GC-content of the genome increases stability in extreme environments. Whole proteome comparisons show the definite archaeal nature of this halophile with additional similarities to the Gram-positive Bacillus subtilis and other bacteria.

bp in size and composed of 3 circular replicons,

a 2,014,239-bp-large chromosome and 2 smaller replicons, pNRC100 (191,346 bp) and pNRC200 (365,425 bp).

of 2,015kb size, a 366kb replicon and a 191kb

replicon. Its replicons have genes for DNA polymerase, transcription factors, mineral (K and PO4) uptake, and cell division. The genomic chromosome has many transposon insertion sites. Halobacterium salinarium carries out aerobic respiration but in water up to 5M (25%!) NaCl (salt). It can be found in the Great Salt Lake in Utah and the Red Sea in Asia Minor.

ml of haloarchaeal culture into fresh medium (e.g. 10

ml of 18% MGM, in a convenient bottle or tube), and shake at 190 rpm, 37°C, for 1 – 2 days, until mid-exponential phase (OD550 of around 0.5 – 0.8).
Take 0.5 – 1 ml sample into a clean 1.5ml microfuge tube and spin cells down (13,000 rpm, 1min, 4°C)

the supernatant as completely (get the last volume out

with a micropipette), then add 80 µl of lysis solution. Pipette up and down to make sure the entire cell pellet is lysed and evenly mixed in the solution, but avoid making air bubbles.

then the cells have not lysed properly. 4. Incubate the

lysed cells at 37°C for 15 min, then place the tube on ice, leave for 2 min. 5. Add 30 µl of ice-cold sodium acetate solution and vortex thoroughly. (keep cold or on ice from now on) 6. Centrifuge the proteins down by spinning at 13,000 rpm, 30 min, 4°C. 7. Remove the supernatant to a fresh tube, add 2 vol of ice-cold ethanol to precipitate the RNA, mix well. 8. Centrifuge at 13,000 rpm, 15min, 4°C. Wash the pellets twice with ice-cold 70% ethanol.

for 30min at RT, dissolve in DEPC-treated water (e.g.

50-100 µl), and store at -70°C. You can also store at -20°C, but preparations last only a few weeks. Determine the yield of RNA by absorption at 260nm (in quartz cuvettes) using the formula 1A260 = 40 µg RNA