Mutagenic Capabilities of
Ethyl-Methanesulfonate
Biology Lab 10501
November 30th, 2016
Lab Group: Drew Garza, Brock Morgan, Christian Chen, Daniel Lee.
ABSTRACT
INTRODUCTION Mutations are permanent changes in DNA sequence that makes up a certain gene that are caused by environmental factors or when DNA is copied in the replication phase. Mutations can range in various sizes and can affect any part of the DNA sequence. In our lab we dealt with Ethyl Methanesulfonate (EMS) and Sega (2015, p.1) stated that “Ethyl Methanesulfonate is a monofunctional methylating agent that has been found to be mutagenic in a wide variety of genetic test systems from viruses to mammals.” In addition (Cameo, p.1) stated …show more content…
typhimurium bacterial strain TA1535 in our screen for mutagens. TA1535 has acquired a missense mutations in the hisG gene which leads to leucine to proline amino acid substitutions. The result of this mutation causes it to be auxotrophic, meaning it cannot survive on its own with histidine. However, the bacteria can be capable to survive on its own in the absence of histidine if it undergoes reversions (mutations that grant them the ability to to produce histidine). In return, we can use the reversion rate to measure and calculate the mutagenic properties of our chemical Ethyl Methanesulfonate. Since EMS is proven and known to acquiring mutagenic capabilities, it should produce reversions in S.typhimurium TA1535 at a frequency comparable to other strong mutagen such as sodium azide or higher than the rate of a spontaneous …show more content…
With the use of three heated top agar solutions, add 100 microliters of the overnight culture as well as 200 microliters of the biotin/histidine solution to each. Each of the three solutions need to be both plated and spread onto minimal glucose agar petri dishes. After the plates have been left to settle for ten minutes, use a sterile filter paper disk to add the positive control of Sodium Azide (NaN3), which is an already known mutagen, into one of the three plates. Continue by doing the same for both the experimental group (Ethyl methanesulfonate) and for the negative control (water). All three plates require an incubation at 37 Celsius for 48
Ethyl-Methanesulfonate
Biology Lab 10501
November 30th, 2016
Lab Group: Drew Garza, Brock Morgan, Christian Chen, Daniel Lee.
ABSTRACT
INTRODUCTION Mutations are permanent changes in DNA sequence that makes up a certain gene that are caused by environmental factors or when DNA is copied in the replication phase. Mutations can range in various sizes and can affect any part of the DNA sequence. In our lab we dealt with Ethyl Methanesulfonate (EMS) and Sega (2015, p.1) stated that “Ethyl Methanesulfonate is a monofunctional methylating agent that has been found to be mutagenic in a wide variety of genetic test systems from viruses to mammals.” In addition (Cameo, p.1) stated …show more content…
typhimurium bacterial strain TA1535 in our screen for mutagens. TA1535 has acquired a missense mutations in the hisG gene which leads to leucine to proline amino acid substitutions. The result of this mutation causes it to be auxotrophic, meaning it cannot survive on its own with histidine. However, the bacteria can be capable to survive on its own in the absence of histidine if it undergoes reversions (mutations that grant them the ability to to produce histidine). In return, we can use the reversion rate to measure and calculate the mutagenic properties of our chemical Ethyl Methanesulfonate. Since EMS is proven and known to acquiring mutagenic capabilities, it should produce reversions in S.typhimurium TA1535 at a frequency comparable to other strong mutagen such as sodium azide or higher than the rate of a spontaneous …show more content…
With the use of three heated top agar solutions, add 100 microliters of the overnight culture as well as 200 microliters of the biotin/histidine solution to each. Each of the three solutions need to be both plated and spread onto minimal glucose agar petri dishes. After the plates have been left to settle for ten minutes, use a sterile filter paper disk to add the positive control of Sodium Azide (NaN3), which is an already known mutagen, into one of the three plates. Continue by doing the same for both the experimental group (Ethyl methanesulfonate) and for the negative control (water). All three plates require an incubation at 37 Celsius for 48