Virulence factors are part of an important concept in bacterial pathogenicity (Henderson, Poole & Wilson, 1996). According to Cross (2008), Dubey and Maheshwari (2013), virulence factors enable the bacteria to produce a variety of molecules in order to adhere, invade and evade host defences and cause tissue damage. these molecules have been grouped into adhesins, invasins, impedins, aggressins and modulins (Dubey & Maheshwari, 2013: Henderson, Poole & Wilson, 1996). Adhesins Adhesins are bacterial proteins that responsible for adhesion to host cells which allow the bacterium to bind to a variety of cells, mainly epithelia, as the first step to entering the host (Dubey & Maheshwari, 2013: Henderson, Poole & Wilson, 1996). Bacteria must adhere
This transformation usually occurs within plasmids, which are closed circular molecules made up of double stranded DNA. The function of the plasmid is to provide bacteria with genetic advantages such as antibiotic resistance. In this lab, the plasmids provided the ampicillin resistance and the fluorescence. If the bacterial cells are grown in the presence of the antibiotic ampicillin then only the cells that took up the plasmid have the resistance gene. As a result the resistance gene will have to keep the plasmid and the GFP gene.
Bacteria taking up foreign DNA is known as transformation. Transformation implies uptake in bacterial, yeast or plant cell DNA while transfection is the term used in reference of mammalian uptake. Chemical transformation, electroporation or particle bombardment is the typical method of construct into a host cell. Conjugation: The easiest illustration is to consider this as a version of bacterial sex. In conjugation the two bacterial cells connect, and the male donates a piece of DNA to the female.
Transfection: One of the methods of gene transfer where the genetic material is deliberately introduced into the animal cell in view of studying various functions of proteins and the gene. This mode of gene transfer involves creation of pores on the cell membrane enabling the cell to receive the foreign genetic material. Transfection can be carried out using calcium phosphate (i.e. tricalcium phosphate), by electroporation, by cell squeezing or by mixing a cationic lipid with the material to produce liposomes which fuse with the cell membrane and deposit their cargo inside. The choice of methods of DNA transfer depends upon the target cells in which transformation will be performed.
Tryptophan is an essential amino acid, which is either synthesized or injested from the environment in bacterial cells.The production of tryptophan is an energy consuming process. So bacteria need to ensure that only when the concentration of tryptophan is low inside cell , it has to produce tryptophan. The trp operon is a repressible system that regulates the biosynthesis of tryptophan. The gene for the repressor is located not near to the promoter,but in a different location.It has an operator which is embedded in the promoter,a leader sequence(trpL) and 5 structural genes(trpE,trpD,trpC,trpB,trpA). Each gene encodes for proteins in the trp synthesis pathway.
It is believed that an endosymbiotic event occurred where an organism capable of oxidative phosphorylation was consumed by another cell. This theory is backed up by the DNA, double membrane and mitochondrial specific transcription and translation mechanisms used to allow such a phenomenon to occur. Mitochondria still secure their characteristic double membrane structure and are still the primary source of ATP production, from their ancestors. Yet, their overall form has been altered, they have acquired innumerable new functions within the cell. The current known structure of Mitochondria is that they are oval in shape and around the same size as a bacterium.
The SYCP1 protein contains a carboxy-terminal domain and an amino-terminal domain that are necessary for interaction with lateral and central elements, respectively. The SYCP1 from transverse filaments interact with the SYCE1 and SYCE2, which are the central elements of the synaptonemal complex (Ding, Da‐Qiao,
The roles are as follows for the bacterial cells, the structure flagella are the swimming movement of the cell, pili stabilizes the cells during DNA transfer, the capsules are used as protection for the cell when a method of killing or digestion is happening. The cell wall confers rigidity and the shape they have, the plasmic membranes are the barriers and the location for the enzyme systems which produces energy. The ribosomes like animal and plant is the factor for protein synthesis. The other functions like the Chromosomes and the plasmid make up the DNA of the cell. Explain how bacteria cells make energy for cellular processes.
The plasmid needs to be isolated from the bacterial cells and the technique used is called alkaline lysis. This technique plays around with the pH to extract plasmid DNA. The culture is grown in medium containing ampicillin to select E.coli that have ampicillin resistance gene as their selectable marker. The addition of detergent to the cells causes cell lysis. The detergent attaches to the cell membrane and capture the protein and lipids of the cell membrane causing the cell to rupture.
Introduction As we all know, bacteria is a very complex organism and the subject can be very broad. In this essay, the focus will be on bacteria and the bacterial cell structure. Different forms of bacteria, its pros and cons, the cell structure, diseases and resistance will be explained and listed. First bacteria and cell structure is explained, and then moving on to different bacterial forms and diseases, and how diseases can be prevented or even cured. Then finishing the essay will be the conclusion.
Tn 4351 was originally isolated from bacteroides fragilis  . The transposon was successfully introduced into Cytophaga succinicans, Flavobacterium meningosepticum, Flexibacter canadiansis, Flexibacter strain SFI and Sporocytophaga myxococcoides by conjugation . Tn 4351carries two antibiotic resistance gene. One of the codes for resistance to erythromycin and clindamycin which is expressed in bactroides but not in E.Coli. The other gene codes for resistance in tetracycline and is expressed in aerobically grpwn E. coli, but not in anaerobically grpwn E. coli or in bacteroides.
Introduction: Transforming a gene or genetic information from one organism into another with the hopes that if done successfully the organism with the new DNA will be given new traits is a method known as genetic transformation (Rafter). Genetic transformation is used quite frequently in today’s world, form medicine to agriculture. In this lab we will be inserting a gene into an Escherichia coli bacteria with the help of a plasmid. Escherichia coli bacteria also known as E. coli, is a bacterium that is rod shaped and contains flagella to help it move. The bacterial DNA is circular inside of an E. coli bacterium.
Selective medium involves medium with environmental conditions that specifically grows some microbes while inhibiting others. Differential medium is used to identify and differentiate (as the title says) closely related microbes based on growth responses and physical indicators. It is imperative to use laboratory positive and negative controls in identifying the unknown because it confirms and compares the results of the unknown’s response to the definite guide. While performing the procedures in this report, students had to keep the bacterial and biological species concepts in context. The bacterial species concept is the identification and naming of microbes based on relating physical and physiological features of the unknown to the fitting taxa.
It also helps to anchor appendages like the pili and flagella; the wall gives the cell its shape and surrounds the cytoplasm membrane, protecting it from the environment. Cell wall of Vibrio cholera protects the cell osmotic shock and physical damage. In addition, it also confers rigidity and shape of bacterial cells. Capsule Some species of bacteria have a third protective covering.Vibrio cholera serogroup O139 does contain a polysaccharide, Capsules keep the bacterium from drying out and to protect it from phagocytosis (engulfing) by larger microorganisms. ( Microbial Biorealm , 2011) Cell membrane The cell membrane is a phospholipid bilayer that completely surrounds Vibrio cholera., The phospholipid bilayer structure has both hydrophilic and hydrophobic, components.