More prominent and visible bacteria. The gram positive bacteria contain a thick peptidoglycan layer in their cell wall which retains the primary crystal violet stain. A suitable ending for this essay might be a quote from Arthur Kornberg, who received the Nobel prize for medicine in 1959. In fact, we are more bacteria than human! It tests the ability of organisms to hydrolyze esculin in the presence of bile. Bacteria, Enterobacteriaceae, Escherichia coli 1053 Words 4 Pages Identification of Two Unknown Species of Bacteria in Tube 72 Introduction: There are many reasons for knowing the identity of microorganisms.
Bacteria, Enzyme, Gram staining 2042 Words 6 Pages a universal method of identifying bacteria allows for all scientists from any part of the world to identify the same species in an identical manner allowing for a precise of classification. The acid fast stain differentiates bacterial cells with lipoidal cell call. Antibiotic resistance, Bacteria, Coagulase 1261 Words 5 Pages Lab Report Microbiology Introduction Bacteria can be found almost anywhere. The microscopic examination of the bacteria after staining allows for the morphology of the organism to be determined because as the cell is killed during the staining process it retains its rigid structure allowing for morphology determination. During the gram stain, lipids are prevalent in the gram negative bacteria are usually transparent as a result of the alcohol decolorizing agent. All those tests are done in laboratories, in hospitals, etc.
Starch agar is an example of differential medium which tests the ability of an organism to produce certain alpha-amylase and oligo-1, 6-glucosidase that hydrolyze starch. Phan Cong Hoang for helpful discussions during the preparation of this thesis report and for providing the bacterial strains. An unknown bacterium was handed out by the lab instructor. Like other bacteria in the Bacillaceae family, B. They still dwell where higher organisms cannot survive, not only on the surface, but also deep in the oceans and in the earth. This is tested on a blood agar plate: a beta-hemolysis creates a white discoloration around the colony whereas an alpha-hemolysis has a brownish green zone around the colony.
The test tube used in this study was tube 109. Staphylococcus aureus can coagulate oxolated plasma and therefore blood. Results Unknown 25 had the following morphology on a streak plate: medium sized butyrous cream colored colony. As a defense mechanism, the host animal produces antibodies anti-X against that bacterium, which remains in the blood. Nathan Cahoone Microbiology 204 December 9, 2010 Introduction There are many reasons for knowing the identity of microorganisms. If the pH is above 7.
The results of the motility test were easiest to determine. And non-medical microbiology faces yet further adversity. It creates a convection current and kills the cells that might have fallen in it during the manipulation. In line with the medically-oriented focus of biological research, a large effort is being made to study the mechanisms of infection of human cells by pathogenic bacteria. The characteristics features of the colonies on solid agar media are then noted. The indicator used is bromothymol blue: the black medium turns blue if the citrate is used. So, the pre-constructed sequence of tests was still performed as if all five of the Gram positive options were still possible.
It has a carbon dioxide generator that converts oxygen into hydrogen and carbon dioxide and a palladium pellet catalyst that takes hydrogen and oxygen to form water. The writing should be simple and easy to understand. Indeed, the non-medical microbiology community has not only studied this symbiotic partnership in ruminants, as can be found in any textbook, but even in protozoa. For healthcare providers it is very important to be aware of what organisms are pathogenic and cause a disease and, therefore, to find an appropriate treatment. Eucaryotic cells can move by means of different locomotor organelles such as cilia, flagella, or pseudopods.
Below is a table of some pathogenic bacteria and their corresponding diseases. This is a test commonly used when trying to identify Gram-negative enteric bacteria, all of which are glucose fermenters but only some of which produce gas. Therefore we must use aseptic techniques. The hydrolysis of urea forms the weak base, ammonia, as one of its products. If you would like to know more about the program, please see the and it. The citrate test determines if a bacterium possess citrate-permease as citrate is the only source of carbon in the medium.
Therefore, different methods of staining exist to be able not only to see but also to differentiate bacteria. The formation of red color after the addition of Methyl red reagent indicates the accumulation of acidic end products in the medium and is an indicative of positive test Fig 4. Two such systems used at present for the automatic identification of bacteria are given as follows: 1. It is now known that good bacteria, or normal microflora, can reach 1014 microbial cells. From the Gram stain slide, you should be able to determine the Gram specificity of your unknown and learn something about the cellular morphology. These will all be very helpful pieces of information in determining your unknown.