Introduction : halophiles are bacteria that tend to be growing in salt concentra

Question

Introduction: halophiles are bacteria that tend to be growing in salt concentration which are more than the concentrations found in oceans. Some of these halophiles require almost saturating levels which would be almost 18-24%. These are referred to as the the Halobacterium. These bacteria would be found in all of the environments that are evaporate and contain salted foods. Some of the most halophiles were where a number of true halophiles, referred to as eubacteria are also present. Most of these could be referred to as chemoheterotrophs, while some of the bacteria make atp with a chemiosmotic proton gradient. As a result of these bacteriorhodopsin, there is presence of pink purple pigments. The environments of halophiles are chemically diverse. The Utah lake has a composition similar to seawater, which would be dominated by the presence of sodium chloride. The concentration is much greater though. Dead Sea has many different salts, whereas, the zugm lake in Africa contains alkaline salts. These halophiles also use inorganic ions in the form of osmotic solutes. thus, in order to start enriching halophiles, concentrated solution of sea water has to be provided along with providing simple or complex sources of carbon along with vitamins as well as trace metals. For enriching alkaliophiles, sodium carbonate has to be used.

Methods: In order to prepare growth medium, sterile water of appropriate volume must be mixed with essential salts at a range of 15-25% while adding calcium chloride at a concentration of 5 ml/L of the solution at a pH range of 7.5-8.5 using tries base. Supplementation of this solution is performed with essential biomolecules such as peptone (5g/L), yeast extract (1 g/L) and glycerol (3 ml/L) and 1.5% agar (w/V) is dissolved for solidification of the media. This suspension is dissolved carefully and autoclaved for sterilization. The sterile media is poured onto culture plates and different types of bacteria are grown using different types of selective salts. The microbes are allowed to grow for an appropriate period of time and visualized under microscope. The small amount of microbe is extracted from the culture plate and transferred onto a sterile coverslip duly sealed using silicone. A visualization stain is prepared by suspending a loop-full amount of microbes into 20% sterile brine, air dried and fixed and sequentially desalted in 2% acetic acid for 5 minutes. The slide is air-dried and washed in crystal violet for 3 minutes, rinsed in double distilled water and air dried. A counterstain is also prepared during the Gram's staining process using fuchsin but it must be carefully noted that the halophiles such as archaea are Gram-negative due to lack of peptidoglycans in their cell wall and do not give true negative Gram-staining results.

please (TYPE) a good results and conculusion for what you see a bove ( see the picture for my result)

Explanation / Answer

Hi,
The naming of the plates is not clearly visible. I assume they are from different lakes. Please correct if not.

Observation: The halophilic bacteria from lake 1 and lake 2, formed colonies on the media plates. The colonies appeared yellow-golden in colour.

Result: The lakes 1 and 2 harbour the culturable halophilic bacteria. These were revived using the cultured media prepared specially for high salt concentration. These colonies can now be picked up and further characterized. The bacteria from other lakes might be cultured if we alter the media compositions to suit them.

Conclusion: The halophilic bacteria belong to the domain of archaea. They are present in the water of extremely high salt content. They can be cultured in the laboratory using specially designed media containing a mixture of different salts, nutrients and vitamins. Gram staining is not advisable as they cannot retain dye for lack of peptidoglycan.

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