13 Questions 19 Answers 0 Followers
Questions related from Luis Peña
The protocol of Thermo Scientific NiNTA resin (cat. 88221) for purification of proteins containing a hexahistidine tag use an elution buffer containing 250 mM imidazole. For fun after this elution...
08 August 2019 6,186 6 View
My experiment involve a dehydrogenase and I would like to identify the optimal substrate. For this an assay was established based on the use of DCPIP as cofactor, which when reduced the absorbance...
01 January 2019 9,523 7 View
My goal is to characterize a dehydrogenase, we are unsure of which cofactor it can uses but we tried DCPIP as artificial redox cofactor and there is no activity. I would like to try phenazine...
06 June 2018 7,280 4 View
I am measuring dehydrogenases enzyme kinetic parameters via Michaelis Mendel fit, the enzyme activity is determined by the inverse of the slope in the absorbance of a redox indicator when this...
05 May 2018 7,022 0 View
I checked the previous answers :) So my enzyme kinetic assay is based on DCPIP absorbance at 3 mM, which is outside of the linear optical range to measure continuously on a plate reader. Then I...
04 April 2018 8,774 9 View
NIST, the National Institute of Standards and Technology publishes reference libraries of hundred of thousand of compounds. I would like to use these in my computer for GC data, however it looks...
04 April 2018 6,586 3 View
In Gao, et al (NAD-Independent L-Lactate Dehydrogenase Required for L-Lactate Utilization in Pseudomonas stutzeri A1501, doi:10.1128/JB.00017-15) CKBB buffer is employed for the optimum pH and...
01 January 2018 4,001 3 View
I have a maltose binding fusion protein being purified with the MBPTrap column (GE). I get very little protein (less than 1 mg from a 400 mL E. coli BL21 (DE3) culture) during the elution step...
11 November 2017 5,732 8 View
What are the advantages and disadvantages of using a volatile or a non-volatile buffer for anion exchange chromatography in an FPLC? Is it only related to further processing , like freeze drying...
11 November 2017 5,492 3 View
The default settings of the FPLC UV detector are for wavelengths 215, 255, 280 and 495 nm. I know that the 280 nm is the most important since it directly measures protein via the aromatic ring in...
08 August 2017 9,893 4 View
I need to retrieve a large list of protein and their related nucleotide sequences. However, batch entrez removes old GI numbers, which in my case are more than half. How can I override this, or...
03 March 2015 7,039 4 View
I'm trying to set up a vital stain protocol with fluorescein diacetate and propidium iodide to verify if a sample of sponge and bacteria cells is still alive after an incubation of 4 months, but I...
10 October 2014 5,386 6 View
I have a few sequences described as enzymes with lypolityc activity and I'm extracting the domains characteristics of said activity using Pfam and MEME (I'm following a procedure described by...
05 May 2013 1,894 5 View