The bacterial species Hongkongia ustii has the following set of characteristics that no other bacterial species has: -being Gram-negative-being resistant to 5% sodium chloride-being able to utilize lactose-causing beta-hemolysis-having optimal growth temperature of 37°C-being facultative anaerobic (i.e. able to grow in the presence or absence of oxygen)-being non-fastidious-having a growth rate similar to that of Escherichia coli-being non-motileQuestion: Design a new medium that enables you to isolate and identify cells of H. ustii in one step from any bacterial extract that may contains many different bacterial species and in which this bacterial species is just a rare one. List out all the medium’s ingredients, each with the amount in gram per liter of the medium.
[size=13.3333px]Explain below:Explanation:To isolate and identify H. ustii in a bacterial extract containing other bacterial species, we need to design a selective medium that allows the growth of H. ustii while inhibiting the growth of other bacterial species.Based on the characteristics of H. ustii, we can design a medium with the following ingredients and amounts (in grams per liter of the medium):Tryptone - 10 gYeast extract - 5 gSodium chloride - 50 gLactose - 10 gBlood agar - 5%Phenol red - 0.025 gAgar - 15 g The above medium is a modification of MacConkey agar, which is a selective and differential medium for gram-negative bacteria. However, MacConkey agar does not contain blood agar, which is needed for detecting beta-hemolysis caused by H. ustii.The above medium contains a high concentration of sodium chloride, which allows the growth of H. ustii but inhibits the growth of many other bacterial species that cannot tolerate high salt concentrations. Lactose is the sole carbon source in the medium, and H. ustii can utilize lactose for growth.The medium also contains blood agar to detect beta-hemolysis, which is a characteristic of H. ustii. Phenol red is a pH indicator that turns yellow when lactose is fermented, indicating the growth of H. ustii.To use the medium, a small amount of the bacterial extract can be streaked onto the surface of the medium and incubated at 37°C under facultative anaerobic conditions. After incubation, the presence of colonies exhibiting beta-hemolysis and lactose fermentation can be confirmed as H. ustii. If face any problem, please comment. my wechat:bbwxnly
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