Ahmed Mohamed Raslan

11 Questions 6 Answers 0 Followers

Questions related from Ahmed Mohamed Raslan

Why my transiton state does not converge?

I am currently working on obtaining the transition state for the deprotonation of a carbocation by histidine. Initially, I froze the bond lengths between the histidine nitrogen and the proton, as...

23 October 2024 2,803 2 View

Is a transition state with constrained bond lengths reliable?

Hi everyone, I have been working on obtaining a transition state for the deprotonation of a carbocation by histidine, where I froze the bond lengths between the histidine nitrogen and the proton,...

22 October 2024 5,551 7 View

Double Voltage clamp: what is source of the current when studying a membrane transporter?

Hello, I'm struggling to comprehend how the current measured in a double voltage clamp experiment corresponds to the entry of ammonium ions while investigating an ammonium transporter. Is the...

06 October 2023 9,454 2 View

How is it possible my flow through has more protein than the lysate?

Hello, "I am observing an unusual phenomenon where the protein concentration in my flow-through sample is consistently higher than that of the lysate sample when run on gel, Still, I am...

13 April 2023 3,917 1 View

Where to find databases of proteins of unknown structures?

Hello, I need suggestions of databases, websites or review articles that have number of proteins of unknown structure. Can you guys recommend me any of these approaches so as to identify a number...

20 January 2023 7,842 0 View

FPLC separation of 30 Kd TAG and 55 Kd target protein?

Hello, I got a question about optimizing my FPLC separation for my 55 kd protein from a pre-attached solubility tag of 30 kd protein. I am using 6x his tag and tev cleavage. After doing the...

22 December 2022 6,304 3 View

How much DNase I (2500 U/ml) to add to 40 ml of protein lysis buffer?

Hello, I have a stock DNase solution of 2500 U/ml, it is supplied as 50% glycerol stocks in 10mM Tris-HCl pH 7.5, 10mM CaCl2, 10mM MgCl2. I need to know how much of this solution to add to about...

21 November 2022 8,426 0 View

Could increased APS concentration result in degraded/ messy protein separation in SDS page?

Hello, Recently I had an issue with polymerization of SDS page. I used to add 5 ul TEMED and 50 ul of 10% APS for each 12 ml of SDS page but suddenly my SDS page stopped polymerizing and could...

09 November 2022 8,188 3 View

I have couple question related to Ligation independent cloning?

I need an explanation of the following paragraph about LIC from a protein expression review article. "For T4 DNA polymerase-based LIC, the 5’ extensions on each primer (of length 12-15 bases) are...

19 July 2022 6,477 0 View

Can anybody explain to me this following statement from a protein expression review article?

"BL21 (DE3)-RIL cells, which are compatible with the T7 promoter system, contain plasmids that encode arginine, isoleucine, and leucine tRNAs that are rare in E. coli, and are deficient in both...

15 June 2022 9,402 3 View

what is the role played by these dialysis buffer reagents ( MOPSO, DTT, glycerol) in TEV protease for purification of His-tagged proteins?

what is the role played by these dialysis buffer reagents ( MOPSO, DTT, glycerol) in TEV protease for purification of His-tagged proteins? also what is the dialysis bag used for?

09 June 2022 8,967 3 View