Gram Positive Bacteria Essay

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The most common bacterial infections that are gram positive are staphylococci which produce enzymes such as catalase which break down hydrogen peroxide bonds, bacillus cereus - food poisoning, bacillus anthracis - anthrax and clostridium tetani - tetanus. Penicillin is an antibiotic that prevents gram positive bacteria from forming peptidoglycan. Peptidoglycan plays a key role in the cell wall. If peptidoglycan was not present, then the bacterium would swell and burst due to the high internal pressure. Cephalosporin is another antibiotic that works against gram positive bacteria as they prevent the bacteria walls from synthesis. Sulfamethoxazole and Sulfisoxazole are antibiotics that are also effective in working against gram positive bacteria. …show more content…
This test is done to determine whether a zone of inhibition is seen. The size of the zone of inhibition will be dependent on how effective the antibiotic is at stopping the bacterium from growing. A strong antibiotic will leave a large zone of inhibition. Penicillin is an antibiotic that works against gram positiveThe gram stain technique is used to distinguish between gram positive bacteria and gram negative bacteria. This technique is used because the gram negative and gram positive bacteria both have different cells wall structures and also respond differently depending on which type of antibiotic they are given. For example, penicillin which is a type of antibiotic will prevent the synthesis of the cell wall in gram positive bacteria however will not work in gram negative bacteria. Penicillin can be used to treat many different infections such as skin infections. Penicillin is an antibiotic that works against gram positive bacteria as it prevents the peptidoglycan from being formed. Daptomycin is another antibiotic which is used against gram positive bacterial infections. This antibiotic can also be used to treat skin infections. The culture should be left in an incubator for at least 24 hours. This is done to allow the agar plate to get used to the environment and also to allow a zone of inhibition to be seen on the agar plate if the antibiotic is …show more content…
This would usually be a bacteria. These samples can then be taken from the colonies and a new microorganism can be grown on a new agar plate. When streak plating is being carried out, you need to ensure the agar plate is dry and there is no moisture present on the agar plate. This is to ensure there is no contamination which could affect the results being obtained. Once the culture has been placed into an incubator, it should be left for at least 24 hours. This is to allow the culture to get used to the environment it is in and to also allow the growth of the microorganism/bacteria. Streak plating is a very easy technique to carry out and the results are provided fairly quickly. Furthermore, it is also very easy to classify microbes using streak plating. Single bacterial or fungal species can be identified based on their morphological differences (size, shape and colour) and then can be sub-cultured to a new media plate to obtain a pure culture for further analysis. The colonies present on an agar plate can be classified depending on many different features. These are the shape, colour and even structure. Many different bacteria colonies are yellow/white in colour and have a circular shape. The different types of colony shapes are circular, irregular, rhizoid and filamentous. If there are 2 types of colonies observed then this would mean the patient has got 2 different infections and thus may need

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