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Description of the problem situation

2.1 Metagenomics

The standard steps of a metgenomics experiment.

 

Craig Venter, the US biologist known for leading the private endeavour to sequence the human genome, is attempting to catalogue the microflora of oceanic environments. Onboard the Sorcerer II, it has already sailed along the east coast of North America, through the Panama Canal and around the Galapagos Islands. Every 200 miles, onboard researchers haul up 200 litres of seawater and filter it for microbes. Samples are frozen and sent to the USA, where biologists at the Institute for Biological Energy Alternatives in Rockville, Maryland, will try to sequence the DNA of every organism in each sample.The expedition has the highest profile among many other similar projects under way around the world, in environments ranging from geographical (abandoned mines) to physiological (the human gut.) After sequencing the DNA of single species (there are complete sequences for more than 300 organisms), researchers are trying to sequence the DNA of living species in defined environments – a science called environmental genomics, or metagenomics. Through better understanding of how myriads of bacteria combine and interact to influence the ocean, we shall be better able to monitor the conditions of these environments and possibly manipulate them to our advantage. It may even be possible to find micro-organisms that can produce drugs or act as energy sources. Science is now able to grow 3,000 species of bacteria on artificial culture media, but the vast majority – probably more than 99 per cent – resist such attempts. It seems impossible to approach such a huge microbial diversity with conventional techniques. Metagenomics can access this information. The principle is simple: select an environment; scoop or scrape up a sample for it; and sequence the genes in that sample. Lab researchers can look for diagnostic DNA sequences to count the number of species in a sample; they can put DNA fragments into bacteria that can be grown in the laboratory, and screen them for properties such as antibiotic production; or they can simply pull out sequences at random to give a picture of the number and type of genes in that environment. In practice, however, there is too much diversity in most environments to sequence every gene of every species. Craig Venter’s team collected a sample of 1,500 litres of water from the Sargasso Sea, in the Atlantic for their global study. They chose the Sargasso Sea because it was presumed to be poor in nutrients, and was thought to be one of the ocean’s less diverse regions. But to their surprise, they found 1,800 species, including 150 new to science, and 1.2 million new genes. Environments richer in nutrients, such as the soil, will probably be even more diverse still. The pilot study in the Sargasso Sea cost $2 million; C. Venter estimates that a more complete scan would currently cost five times that. The US Department of Energy funded the Sargasso Sea project. Thorough surveys of such places will have to wait for expected falls in the cost of sequencing. Metagenomics could help us understand environmental problems such as carbon dioxide take up by bacteria to reduce its concentration, the breakdown of pollutants by micro-organisms, It could also help to detect environmental damage, because once we know what it is that is out there, it is a step to be able to determine any changes to the environment. Biotechnology companies such as Diversa, based in San Diego, are also working to mine the data for useful genes. A new antibiotic, turbomycin, was recently discovered during a metagenomic scan of soil by a team led by Jo Handelsman at the University of Wisconsin, Madison. For the time being, C. Venter’s main objective is to gather information: ‘the main purpose is cataloguing what is here and the diversity is higher than most people imagined; we are spending billions looking for life in Mars, but we do not have the slightest idea of what life there is on this planet’.



 

 

3. Tasks to case.

Test

1. Lack " of absolute filters ":

 

a) Large resistance

 

b) Low efficiency

 

c) Are sensitive to a moisture

 

d) Are inconvenient in operation

 

e) Are suitable only for clearing liquids

 

2. Metobolism - set of consecutive biochemical reactions:

 

a) Proceeding in a crate during its ability to live

 

b) Proceeding in fermenter

 

c) Proceeding without participation ferment

 

d) Organic acids, resulting in formation

 

e) Resulting to formation metoboli

 

3. Bioshrot is:

 

a) Waste of microbiological manufacture

 

b) Raw material for microbiological manufacture

 

c) Component of nutritious environment

 

d) Biological agent for preparation of vaccines

 

e) Viruscontaining a preparation

 

4. Aerob - microorganism requiring for the ability to live :

 

a) Free molecular oxygen

 

b) Absence of oxygen

 

c) Additives of mineral substances

 

d) Hydrogen or carbonic gas

 

e) Various to simbiotic

 

5. The aerofilter is:

 

a) Biofilter with compulsory aeration

 

b) Filter established on air stations

 

c) Biofilter for clearing waste water

 

d) Biofilter for cultivation of microorganizm

 

e) Filter with compulsory circulation of a liquid

 

6. Bacterial leaching is:

 

a) Selective extraction of microorganisms, chemical elements from multicomponent connections

 

b) Dissolution of connections in water environment

 

c) With application of simultaneous influence of alkali and temperature

 

d) Dissolution in water environment of various biological objects under action of alkali

 

e) All answers are not correct

 

7. Perkolyacional hydrolysis of wood will carry out:

 

a) Diluted sulfuric acid

 

b) Concentrated hydrochloric acid

 

c) Diluted alkali

 

d) Concentrated alkali

 

e) Water

 

8. At coproduction of spirit and yeast the output of sivush oils on one ton of an absolutely dry product makes, kg:

 

a) 0,3

 

b) 1

 

c) 20

 

d) 25

 

e) 10

 

9. At increase of viscosity of environment :

 

a) Is at a loss diffuzia

 

b) Grows ðÍ

 

c) Decreases ðÍ

 

d) The process of hashing is facilitated

 

e) The microorganisms at once perish

 

10. Many mineral salts can:

 

a) To form distribution of charges on a surface of microorganisms

 

b) To reduce nutritional value substrate

 

c) To not be dissolved in nutritious environment

 

d) Considerably to change ðÍ

 

e) To form whey

 

11. The chemical methods of synthesis have advantages above biotransformation:

 

a) It is easier to allocate a product from more concentrated solutions

 

b) Specificity of action ferments

 

c) Soft conditions

 

d) Necessity of creation aseptic of conditions

 

e) Small quantity wastes

 

12. At hydrolysis of peat apply:

 

a) Periodic hydrolysis

 

b) Burning raw material

 

c) Percoliacia

 

d) Addition acetone

 

e) There is no correct answer

 

13. For dezintegraci the bioweights with the purpose of allocation from it of a final product can be applied:

 

a) Litic enzyme

 

b) Hashing

 

c) Antibiotics

 

d) Glucose

 

e) Anyone enzyme

 

14. The stability of ground is …

 

a) Ability of ground to keep in conditions of anthropogenous influence structure and properties

 

b) Change of properties under influence of anthropogenous influences

 

c) Aility of ground to self-restoration

 

d) Ability of ground to counteraction on negative anthropogenous influences

 

e) All answers are not correct

 

15. Continuous methane fermentation goes at temperature:

 

a) 53 – 55Ñ

 

b) 100 – 150Ñ

 

c) 5 – 10Ñ

 

d) 1 – 2Ñ

 

e) 20 – 25Ñ

 

 

Conclusion

The potential of ‘white’ biotechnology is conducive to the tie-ups and linkages among government, industry and academe to work within a sustainable development framework. By providing alternatives such as new materials and fuels that are not derived from petrochemical processes, by improving and enhancing the bioremediation of water, soils and ecosystems at large, by trying to use less fossil-fuel energy, ‘white’ biotechnology will enjoy a positive social acceptance, even among environmentalists, if it continues on this path. However, a crucial factor in social acceptance particularly by environmentalists is the conclusive impact on biodiversity of releasing into the environment genetically-modified organisms used in the processes of ‘white’ biotechnology, including bioremediation; and this is still largely unknown. Industrialists use “white biotechnology” mostly in confined environments, such as their factories, bioreactors and greenhouses, while applying strict biosafety regulations. Until then, widespread social acceptance may have to wait.

 


Date: 2015-04-20; view: 999


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