Detecting Bacterium that Cannot be Cultured Assignment

Detecting Bacterium that Cannot be Cultured Assignment

How can you detect the presence of bacterium that cannot be cultured? Explain your answer with specific examples

The first bacterial culture media were broths made either by infusion or by enzymatic digestion of meat from various sources. Originally developed by Spallanzani in the 18th century and then refined by Pasteur in the 19th century, these allowed the recovery of bacteria from human disease sites1,2. However, it was quickly realized that such broths would be likely to contain mixtures of micro-organisms, and Robert Koch saw the need for development of solid culture media that would allow the physical separation of bacterial colonies. He first tried aseptically divided potatoes. Material taken from infected lesions was spread across the potato and then incubated at body temperature. Following incubation, bacterial colonies were seen which could be subcultured to further potatoes to give pure cultures. Although successful, Koch observed that only a limited number of the micro-organisms present in the sample grew on the potato. This was probably the first recognition of the phenomenon of unculturability in vitro. Nevertheless, the success of the technique led to the use of solidifying agents such as gelatin and agar to create solid media from the broths developed by Pasteur and others. This advance led to the golden age of medical microbiology, in the last quarter of the 19th century, when many of the bacteria causing serious infections in man were identified. This tremendous success, however, probably led microbiologists to become complacent simply because so many important pathogenic bacteria could be cultured in vitro in this way.

Important information for writing discussion questions and participation

Welcome to class

Hello class and welcome to the class and I will be your instructor for this course. This is a -week course and requires a lot of time commitment, organization, and a high level of dedication. Please use the class syllabus to guide you through all the assignments required for the course. I have also attached the classroom policies to this announcement to know your expectations for this course. Please review this document carefully and ask me any questions if you do. You could email me at any time or send me a message via the “message” icon in halo if you need to contact me. I check my email regularly, so you should get a response within 24 hours. If you have not heard from me within 24 hours and need to contact me urgently, please send a follow up text to

I strongly encourage that you do not wait until the very last minute to complete your assignments. Your assignments in weeks 4 and 5 require early planning as you would need to present a teaching plan and interview a community health provider. I advise you look at the requirements for these assignments at the beginning of the course and plan accordingly. I have posted the YouTube link that explains all the class assignments in detail. It is required that you watch this 32-minute video as the assignments from week 3 through 5 require that you follow the instructions to the letter to succeed. Failure to complete these assignments according to instructions might lead to a zero. After watching the video, please schedule a one-on-one with me to discuss your topic for your project by the second week of class. Use this link to schedule a 15-minute session. Please, call me at the time of your appointment on my number. Please note that I will NOT call you.

Please, be advised I do NOT accept any assignments by email. If you are having technical issues with uploading an assignment, contact the technical department and inform me of the issue. If you have any issues that would prevent you from getting your assignments to me by the deadline, please inform me to request a possible extension. Note that working fulltime or overtime is no excuse for late assignments. There is a 5%-point deduction for every day your assignment is late. This only applies to approved extensions. Late assignments will not be accepted.

If you think you would be needing accommodations due to any reasons, please contact the appropriate department to request accommodations.

Plagiarism is highly prohibited. Please ensure you are citing your sources correctly using APA 7th edition. All assignments including discussion posts should be formatted in APA with the appropriate spacing, font, margin, and indents. Any papers not well formatted would be returned back to you, hence, I advise you review APA formatting style. I have attached a sample paper in APA format and will also post sample discussion responses in subsequent announcements.

Your initial discussion post should be a minimum of 200 words and response posts should be a minimum of 150 words. Be advised that I grade based on quality and not necessarily the number of words you post. A minimum of TWO references should be used for your initial post. For your response post, you do not need references as personal experiences would count as response posts. If you however cite anything from the literature for your response post, it is required that you cite your reference. You should include a minimum of THREE references for papers in this course. Please note that references should be no more than 5 years old except recommended as a resource for the class. Furthermore, for each discussion board question, you need ONE initial substantive response and TWO substantive responses to either your classmates or your instructor for a total of THREE responses. There are TWO discussion questions each week, hence, you need a total minimum of SIX discussion posts for each week. I usually post a discussion question each week. You could also respond to these as it would count towards your required SIX discussion posts for the week.

I understand this is a lot of information to cover in 5 weeks, however, the Bible says in Philippians 4:13 that we can do all things through Christ that strengthens us. Even in times like this, we are encouraged by God’s word that we have that ability in us to succeed with His strength. I pray that each and every one of you receives strength for this course and life generally as we navigate through this pandemic that is shaking our world today. Relax and enjoy the course!

Hi Class,

Please read through the following information on writing a Discussion question response and participation posts.

Contact me if you have any questions.

Important information on Writing a Discussion Question

• Your response needs to be a minimum of 150 words (not including your list of references)
• There needs to be at least TWO references with ONE being a peer reviewed professional journal article.
• Include in-text citations in your response
• Do not include quotes—instead summarize and paraphrase the information
• Follow APA-7th edition
• Points will be deducted if the above is not followed

Participation –replies to your classmates or instructor

• A minimum of 6 responses per week, on at least 3 days of the week.
• Each response needs at least ONE reference with citations—best if it is a peer reviewed journal article
• Each response needs to be at least 75 words in length (does not include your list of references)
• Responses need to be substantive by bringing information to the discussion or further enhance the discussion. Responses of “I agree” or “great post” does not count for the word count.
• Follow APA 7th edition
• Points will be deducted if the above is not followed

• Remember to use and follow APA-7th edition for all weekly assignments, discussion questions, and participation points.
• Here are some helpful links
• The is a great resource

Go to:
UNCULTURABILITY
We are grossly ignorant of bacterial life on earth. Environmental microbiologists estimate that less than 2% of bacteria can be cultured

in the laboratory. In the mouth we do rather better, with about 50% of the oral microflora being culturable3. For other body sites, the figure is unknown but is likely to be similar to that found in the mouth or higher. For example, the colonic microflora is suspected to be predominantly unculturable. It is therefore likely on numerical grounds alone that unculturable and therefore uncharacterized organisms are responsible for several oral and other human infections. A known instance is syphilis, caused by the spirochaete Treponema pallidum, which remains unculturable today.

Go to:
MOLECULAR IDENTIFICATION OF BACTERIA
It is only with the advent of molecular biology that techniques have become available for studying mixed bacterial communities in their entirety, without the biases of culture. The theoretical basis for the development of these methods came first from Zuckerandl and Pauling4, who suggested the use of biological macromolecules for the elucidation of evolutionary relationships among organisms. This idea, which developed into the branch of science known as molecular phylogeny, relies on the analysis of the DNA sequences of genes of common ancestry, or proteins themselves, in a range of organisms. Mathematical techniques are used to assess the similarity of these sequences and to construct phylogenetic trees which demonstrate the evolution of the whole organisms from which the DNA or proteins were isolated. In practice, ‘housekeeping’ genes are used for this purpose since they are widely distributed among different organisms and because their essential function has made them relatively conserved throughout evolution, allowing easy alignment of the sequences. The most widely used of these genes to date has been the small subunit (16S) ribosomal RNA gene5. At around 1500 base pairs in length this is both long enough to be informative and short enough to allow easy sequencing, particularly since the advent of automated DNA sequencers. Phylogenetic trees are constructed by first aligning sequences of the same gene from different organisms. Then the genetic distance between pairs of organisms in the dataset is calculated to give a matrix of similarities. This matrix is then further analysed by, for example, the neighbour-joining method in order to construct the phylogenetic tree or dendrogram6