MICROBIOLOGY FOR STUDENTS (M4S)

TaqMan PCR is another target specific real-time PCR technique. The technique takes use of the Taq polymerase's 5′→3′ nuclease activity to identify and quantify specific PCR products as the reaction progresses. A nucleic-acid probe complementary to an internal region of the target DNA is used in TaqMan PCR. The internal TaqMan probe is coupled with a reporter fluorochrome and a quencher fluorochrome. The fluorescence generated by the reporter fluorochrome is absorbed by the quencher fluorochrome as long as the two fluorochromes are in close proximity. Thus, two fluorescent moieties are attached to the probe and the emission spectrum of one fluorophore overlaps the excitation spectrum of the other, causing the first fluorophore to be “quenched” by the second. If product is produced, the probe is destroyed by Taq polymerase's 5′-nuclease activity (Tyagi and Kramer 1996), which is specific for DNA hybridized to template (=TaqMan activity). The probe's deterioration allo...

Transformation Experiment on E. coli with pGLO | M4S Digital Textbook M4S Microbiology for Students Print Top Molecular Biology • Digital Learning Chapter Transformation Experiment on E. coli with pGLO Plasmid A structured M4S learning chapter covering plasmids, transformation, the arabinose operon, GFP, pGLO characteristics and interpretation of the supplied transformation results. 7 Chapters Molecular Biology Student Notes M4S Expand All Collapse All Clear Search Reading progress: 0 of 7 chapters opened Contents Plasmid Transformation Arabinose Operon GFP pGLO Results References 1 Introduction to Plasmids ⌄ A plasmid is a piece of extrachromosomal DNA present in bacteria that is capable of self-replication. The supplied source describes plasmids as genetic tools that can be introduced into bacteria through transformation and used to express genes and produce proteins. Key point: The source identifies fertility F-plasmids, resistance plasmids, virulence plasmids, d...

Preparation of Template DNA by Boiling Method Preparation of Template DNA by Boiling Method S. No. Procedure 1 A single bacterial colony from overnight culture is suspended in 100 µL of 50 mM concentration of NaOH taken in eppendorf tube. 2 The tube is kept in a water bath at 97ºC for 3 minutes after properly sealing with paraffin tape. 3 Then the tube is placed into the refrigerator at 4ºC for 5 minutes. 4 After refrigeration, 16 µL of 1M of Tris-HCl is added and centrifuged at 8000 rpm for 2 minutes. 5 The supernatant is transferred and stored at -20 o C. References S. No. Papers 1 Hartas J, Hibble M, Sriprakash KS. Simplification of a locus-specific DNA typing method (Vir Typing) for Streptococcus pyogenes. J Clin Microbiol. 1998;36:1428-29.

Bacterial Toxins | M4S Digital Textbook M4S Microbiology for Students Digital Textbook Bacteriology • Digital Learning Chapter Bacterial Toxins Types, characteristics, examples, and comparison of bacterial exotoxins and endotoxins. 7 Chapters Microbiology Student Notes M4S Expand all Collapse all Clear search 0 of 7 chapters opened Jump to a chapter… Contents 1. Introduction 2. Exotoxins 3. Endotoxins 4. Enterotoxins 5. Cytotoxins 6. Hemolysins 7. Comparison & References 🦠 1. Introduction › Bacteria produce various toxins that play critical roles in their pathogenicity and virulence. These toxins can cause harm to host cells and tissues, leading to a range of symptoms and diseases. Core classification: The supplied source groups bacterial toxins into two primary groups: exotoxins and endotoxins . It also describes enterotoxins, cytotoxins, and he...

Prepared By: Ms. Hira Sakha   Edited and Updated By: Mr. Bikram Malla

Severe coronavirus disease 2019 (COVID-19) is well known for pneumonia, lymphopenia, exhausted lymphocytes, and a cytokine storm. The significant antibody production whether protective or pathogenic in nature is yet to be determined [1]. Most patients with COVID-19 exhibit mild to moderate symptoms. However, approximately 15% progress to severe pneumonia and 5% eventually develop acute respiratory distress syndrome (ARDS), septic shock, and/or multiple organ failure [2-3].

Prior the development of any anti-viral agents or vaccine, the initial step requires comprehensive understanding of viral replication process that augments the number of viral copies in the host cell. The replication of typical virus has following step in their lifecycle are (1): 1. Attachment and entry 2. Uncoating 3. Gene expression 4. Genome replication 5. Assembly and maturation 6. Egress and release