Need help figure out the order of GENES.
Okey here is the info
Bacterial cells of genotype pur- pro+ his+ were transduce with P1 bacteriophage grown on bacteria of genotype pur+ pro- his-. Transductants containing pur+ were selected and tested for the unselected markers pro and his. The number of pur+ colonies with each of the four genotype were as followed:
pro+ his+ 102
pro- his+ 25
pro+ his- 160
pro- his- 1
what is the gene order?
To determine the gene order, we need to analyze the results of the transduction experiment. From the given data, we can see the number of pur+ colonies with different combinations of pro and his genotypes.
Let's start by analyzing the results:
- pro+ his+: This genotype has 102 colonies.
- pro- his+: This genotype has 25 colonies.
- pro+ his-: This genotype has 160 colonies.
- pro- his-: This genotype has 1 colony.
To determine the gene order, we need to compare the results for the different genotypes. Let's examine the data step by step:
1. First, we compare the pro+ and pro- genotypes while keeping the his genotype constant.
- pro+ his+: This genotype has 102 colonies.
- pro- his+: This genotype has 25 colonies.
From this comparison, we can see that the presence of the pro+ gene increases the number of colonies compared to the pro- gene. Therefore, we conclude that the pro+ gene is located upstream of the pro- gene.
2. Next, we compare the presence or absence of the his gene while keeping the pro genotype constant.
- pro+ his+: This genotype has 102 colonies.
- pro+ his-: This genotype has 160 colonies.
From this comparison, we can see that the presence of the his- gene increases the number of colonies compared to the his+ gene. Therefore, we conclude that the his- gene is located upstream of the his+ gene.
Putting all the information together, we can determine the gene order:
pur- his- pro+ his+
So, the gene order is pur- his- pro+ his+.