Question

In Bacillus subtilis, linkage analysis of two mutant genes affecting the synthesis of two amino acids, tryptophan \(\left(t r p_{2}^{-}\right)\) and tyrosine \(\left(t y r_{1}^{-}\right),\) was performed using transformation. Examine the following data and draw all possible conclusions regarding linkage. What is the purpose of Part \(\mathrm{B}\) of the experiment? [Reference: E. Nester, M. Schafer, and J. Lederberg (1963).]

Short answer

What is the purpose of Part B of the experiment? Answer: With the information provided, we cannot draw any conclusions regarding the linkage between the trp2- and tyr1- genes in Bacillus subtilis, as there is no data available for analysis. Similarly, we are unable to determine the purpose of Part B of the experiment without additional information about its design and objectives.

Step-by-step solution

Examine the given data

For this exercise, we need to examine the available data to determine if there is any evidence for linkage between the tryptophan (trp2-) and tyrosine (tyr1-) genes in Bacillus subtilis. Unfortunately, there is no data provided. In a normal case, we would have to analyse the data showing the transformation frequencies and occurrences of different phenotypes in the transformed bacterial population.

Analyze the results and draw conclusions about linkage

Given the absence of data, we cannot analyze the results or draw any conclusions about the linkage between the two genes. If we had the data, we would look for patterns showing the co-transformation of both genes, indicating that the genes are closely located on the chromosome and thus linked.

Explain the purpose of Part B of the experiment

Without knowing what Part B of the experiment involves, we cannot definitively explain its purpose. Generally, Part B of such an experiment might be designed to validate the findings of Part A and provide additional evidence for linkage or to rule out other explanations for the observed co-transformation. In conclusion, based on the available information, we cannot draw any conclusions regarding linkage between the trp2- and tyr1- genes in Bacillus subtilis, nor can we determine the purpose of Part B of the experiment.