How to increase the pH tolerance of an Enzyme ?

There is an enzyme which pH optima is 6.5, we want to make this enzyme working well at pH 4.5, without disturbing its catalytic efficiency for a reason of industrial fermentation process. The...

06 July 2018 8,909 6 View

Is it possible that Km of key residue mutant is similar to wild type enzyme ?

I am getting Km value of a mutant which is similar to its wild type. How it is possible ? The residue is quite important for substrate binding. Is it possible ? please suggest !

10 November 2017 5,476 4 View

Is it fine to mutate some conserved residues in the active site ?

I am planning to make the wild type enzyme pH tolerant (acidic) without affecting the activity of the native enzyme. Here i am thinking to introduce some residues like lysine or ariginine in place...

08 September 2017 1,322 5 View

Which tool is best for showing secondary structure element on the sequence alignment other than ESPRIPT (which can use the pdb file to do it) ?

I am trying to find some tool or server which put secondary structure elements on top of the sequence alignment which ESPRIPT does very well. But is there any other tool which I can use to show...

02 March 2015 712 5 View

Why the protein after Site Directed Mutagensis is not expressed ?

I have done whole plasmid amplication using XT-20 high fidelity enzyme from merck. After induction with 0.3mM IPTG i did not see any expression of the protein.I am suspecting some mutation has...

01 February 2015 3,091 6 View

How can I isolate double stranded DNA from single stranded in a mixture?

09 October 2014 6,666 5 View

Why is the Difference between Rwork and Rfree 10% when refined at 3.2 Angstrom?

I am little bothered that my structure refined at 3.2 Angstrom, have a difference of 10 % without and with solvent contents. The difference is not changing. completeness is 97.6 % at 3.2 Angstrom....

06 July 2014 6,790 8 View

How does one shade the conserved and non-conserved protein sequences after MSA?

I have used a boxshade server, but here I am finding difficulties as it puts sequence numbers here and there after the job. So does anybody have an idea to do the same without any erroneous job of...

06 July 2014 9,086 4 View

What is "Refmac sigma-AA weighted map data"?

06 July 2014 7,131 5 View

How to improve the quality of my crystal?

As I have purified my protein and set crystallization screen and I tried various way to optimize the crystal quality, such as seeding, changing pH, PEG concentration, salt concentration and...

04 May 2014 8,551 10 View

How to compare 2 samples recruited with different sampling methods?

If I want to compare characteristics of 2 groups of patients, one group is recruited from a random sample of the general public while another group is from a sample with a fixed gender (male to...

26 February 2021 3,526 3 View

Do you consider undergoing a structure literature review / Meta analysis and getting numerical findings sort of quantitative method?

I am looking for a classification of the research methods included in literature review papers or Meta analysis ones .

22 February 2021 1,131 4 View

Can I do two kinds of mixed method in explanatory research?

Dear distinguish professors and scholars, I have a research in measuring two kinds: think tank capacity and research impact on policy. Can I do two kinds of mixed methods in order to find, "Is...

20 February 2021 6,897 1 View

How to analyse a (perceptual) study using differing/comparable sets of stimuli?

I plan on running an online perceptual experiment that has, let's say, 100 unique video stimuli altogether. Since these are too many to be rated by every participants, I would like to present the...

15 February 2021 7,444 2 View

How to analyse a split-plot design in stata ?

I have run an split-plot design experiment evaluating the efficacy of a treatment (with 3 whole plots and 4 sub-plots), and I am planning to analyse the collected data in Stata. However, I do...

14 February 2021 7,800 7 View

Can I use a likert survey for criterion sampling in a qualitative study or would that make it mixed methods?

I am doing a phenomenographic study on the reading experiences of avid v. Neutral v. Non-Readers. If I use a likert survey to criterion sample for participants, does that make it a mixed method...

09 February 2021 8,594 3 View

How to create the context-mechanism-outcome configuration (CMOc) in the realist methodology?

In the realist methodology (especially by Raymond Pawson et al), the CMOc is a common structure to explain what works, for whom, in what circumstances, and why? I'm always asked about the...

08 February 2021 2,792 1 View

Recommendations for sample size in visual qualitative research (using children's drawings)?

Hi everyone! Asking for a little help, if I may. I am working on a research project, where I aim to analyse children's drawings about Covid-19. I am fairly new to using visual data in qualitative...

07 February 2021 9,530 3 View

How do I create a categorical variable, level of exposure, and a dummy dichotomous, yes-no, variable for the Harvard Trauma Questionnaire Part 1?

I am using the Harvard Trauma Questionnaire (HTQ) Trauma Events scale (original version) that has 17 items (17 different traumatic events) with 4 response options, indicating 4 levels of exposure:...

04 February 2021 1,509 3 View

How to report path analysis / SEM with Yuan-Bentler correction from R output?

Dear all, I am currently writing my master thesis where I am analysizing my data using path analysis and SEM in R (lavaan package). Now that I like to write up my results, I am struggling with...

04 February 2021 8,993 2 View