Identification of unknown bacterial cultures

Identification of unknown bacterial cultures

identification of unknown bacterial cultures is one of the major responsibilities of a microbiologist. Samples of blood, tissue, food, water and cosmetics are examined daily in laboratories around the world for the presence of contaminants. Industrial and medical microbiologists are constantly screening materials for new isolates that may produce useful products. Whatever the purpose, an unknown bacterium once isolated must be identified and classified.

Bergey’s Manual of Determinative Bacteriology is the official and internationally accepted reference for bacterial classification since 1923. In Bergey’s Manual, related bacteria are arranged into groups or sections. The interrelationship of the bacteria in each section is based on characteristics such as morphology, staining reactions, nutrition, culture characteristics, and biochemical tests. This manual is an important tool to aid microbiologists in their identification of unknown bacterial cultures.

 

What are 3 tests we could use to identify an unknown bacteria?

Identification of unknown bacterial cultures

The purpose of this Unknown Project is to allow you to apply the laboratory techniques you have learned and use them to characterize and identify an unknown bacterial isolate. You will be assessed for concise documentation of lab work in a “lab journal”, interpretation of results and logical justification for the ‘path’ that is taken in your project to identify the unknown. Several copies of Bergey’s Manual are available in the micro lab for use in the lab only. Bergey’s Manual will be the information source for creating dichotomous keys for the elimination process to identify your unknown.

 

Identification of unknown bacterial cultures: Formal Summary of Biochemical Analysis of Unknown

Identification of unknown bacterial cultures
Written summary analyzing results and explaining why particular lab tests were chosen to show the process used to identify your unknown. Explain how you arrived at a Bergey’s Grouping, then a Genus then a species as opposed to explaining results in chronological order. Discuss the test results used to decide why certain genera were being considered in your determination and why particular genera could be eliminated at each stage of the project. Discuss whether test results were reliable or not and troubleshoot any conflicting data. End with the final Unknown identification as determined by your lab tests.
Summary Table of all FINAL test results. This should include cell shape and arrangement, staining characteristics, biochemical test results and growth characteristics on special media as well as BLAST analysis. Do not report repeated test results.
Dichotomous tree/flowchart (can be hand-drawn and scanned or photographed) showing YOUR path for eliminating various organisms. List all groups, genera, or species that are eliminated.
Molecular Analysis of Unknown
State the name of the organism identified by BLAST search of the nucleic acid sequence given to you. Indicate what nucleic acid sequence is being compared and on what database. Include a screenshot of the BLAST results of the top 10-15 organisms with the highest % identity and highlight YOUR ORGANISM.