Culture dependent vs culture independent methods - Lab Report Example

MICROBIOLOGY QUESTIONS Questions Outline the different bacterial species in the oral cavity as detected by 16S rRNA sequencing and culture-dependent traditional microbiology. Are there any similarities amongst the groups of bacteria detected by one identification method and not the other?Some of the bacterial species detected by 16 S rRNA included, Actinomyces, Corynebacterium, Rothia, Propionibacterium, Atopobium amongst other highlighted by the graph above. As for culture-dependent bacteria, staphylococcus forms the predominant group.

It is however worth noting that majority of the culture-dependent bacteria also got detected by 16S rRNA (Goldenberger, 1997 p. 104).2. How do culture-dependent traditional microbiology and 16s rRNA sequencing avoid contamination of the identification process by viral or human material?Some of the techniques that can be applied include, but not limited to performing rDNA PCR amplification on clinical specimens regarded sterile, such as blood. It is however advisable that this technique should not be employed with specimens originating from nonsterile sites such as faeces (Litton, 2010 p. 56). Collection of specimens such as conventional assays needs aseptic precautions.

Litton (2010, p.57) claims that in order to curb contamination DNA brought by specimen collection vials, ensuring that the environment where work goes on is well organised also helps with this. Contamination linked to personnel working in the laboratory can be avoided by wearing cloves made of gloves or latex plus white coats. As for those contaminations resulting from consumable reagents and plastic wares, prior screening of each and every reagent before use in diagnostic assays (Litton, 2010 p. 56).3.

Find at least one peer-reviewed scientific research article regarding the bacteria that normally reside in the human mouth and provide references. Describe the groups of bacteria these studies identified to be present in the human mouth.Some of the bacteria that reside in the mouth include but not limited to, staphylococcus with the most common ones being S.epidermidis and S.aureus. They are oval in shape and posses a thick cell wall, named gram-positive. They cause infections in human population when presented with optimal conditions (“New bacterial species found in human mouth” 2008, p.26).Bacteria from the genus streptococcus forms the largest number of all the organisms found in the mouth.

Some of the species here include, but not restricted to, S. mutans, S. mitis, S. salivarius, S. pneumoniae and S. Pyogenes. They are also oval in shape like the staphylococcus. S.mutans is also responsible for cavity formation in teeth by converting sucrose sugar into lactic acid which thereafter eats away the enamel down to the gum tissue.According to “New bacterial species found in human mouth” (2008, p.26) members of the lactobacillus genera breaks down lactose into lactic acid thus causing teeth cavities.

Members of this group are long and rod-like in shape and also possess thick cell wall. 4. How do these lists of bacteria you identified in Question 3 compare with the list we compiled through culture dependent and culture independent identification techniques in Project 3? Why might our list of bacteria be different from theirs?It is evident that the above described bacteria are also found under the culture dependent bacteria techniques. The list might vary because the culture independent bacteria require the use of complicated media to copy the conditions found at the site of isolation or the employment of co-culture approaches (Snedden, 2000 p. 15).5.

Describe 2 advantages that 16s rRNA sequencing has over traditional culture-dependent techniques in bacterial identification. Why is it still important to know how to do traditional culture-based bacterial identification?Some of the advantages are; it has a single protocol that is easy to learn and with a relatively high through put, as a result of this, substantial degree of identification is expected. Secondly, 16S rRNA has sufficient size which means it can contain enough information that are of benefit when it comes to identification and analysis of phylogeny (Kabbes, 2007 p. 76).References“New bacterial species found in human mouth” 2008, Biology in nature, vol 3,p.26. Goldenberger, D. (1997). Detection of bacterial pathogens in clinical specimens by broad- range PCR amplification and direct sequencing of part of the 16S rRNA gene. S.l.: [s.n.].Kabbes, K. C. (2007).

Restoring our natural habitat proceedings of the World Environmental and Water Resources Congress 2007, May 15-19, 2007, Tampa, Florida, USA. Reston, Va.: American Society of Civil Engineers. Litton, R. M. (2010). Water quality impacts of raw and treated sewage on designated marine and freshwater recreational sites and beaches. Irvine, Calif.: University of California, Irvine.Snedden, R. (2000). The benefits of bacteria. Chicago, Ill.: Heinemann Library.