Does formaldehyde fixation affect bacterial cell morphology/nucleoid condensation?

We work with a difficult-to-stain Gram-negative bacterium. We need to stain the membrane and nucleoid with different dyes (unfortunately, we cant use the FM series of membrane dyes from...

03 April 2019 9,171 2 View

Maximum size for Overlap extension PCR (SOEing PCR)?

I have a gene that I need synthesized that is about 4150 bp long. Getting it synthesized completely in one piece will be expensive and time-consuming. I've used overlap PCR before to make ~1000 bp...

10 November 2017 5,299 4 View

Does anyone have a protocol for staining gram negative bacteria with the membrane stain DiI-C18?

Currently, I stain with 1-5 ug/mL DiI-C18 for 30 mins at 37oC, but most of the cells aren't staining. I can't fix my cells, because my cells express GFP and I've noticed decreased GFP signal after...

01 January 1970 9,365 1 View

Is it possible to use DAPI and PI simultaneously?

I'd like to stain bacterial cells to see all of the cells' nucleiods along with which cells have disrupted membranes. Can DAPI and PI be used in the same cells? I know their emissions are very...

01 January 1970 1,694 4 View

Looking for Materials with high thermal expansion coefficient and high temperature resistance?

03 March 2021 8,272 1 View

Does anyone have a recommendation for yeast reporter gene plasmid/protocol?

Hi, could anyone recommend a plasmid and/or protocol for reporter gene assay in S. cerevisiae? I want to assess the effect of growth conditions on a transcription factor, so I want to clone it`s...

01 March 2021 210 1 View

How to grow E.coli on the low salt LB agar plate with 50 or 100ug/ml of Blasticidin?

Hello, I would like to ask how to grow E.coli which resists 50 or 100ug/ml of Blasticidin. I have tried many methods by using low salt Luria-Bertain(LB) agar plate. However, no colonies grow. Let...

01 March 2021 2,027 2 View

Why might my GFP tag be dissociating from my plasmid after transfection?

I have a set of stably transfected cell lines all transfected with plasmids containing GFP tags on the C terminus. During a western blot using anti-GFP antibody, one of my plasmids has dissociated...

01 March 2021 9,310 4 View

Expression cloning by using cDNA,do I need to modify the cDNA first?

I am going to have a expression cloning of mammalian gene by using shuttle plasmid to transforming the E.coli However I don't know I should only inserting the Coding sequence ,or I can...

28 February 2021 5,440 3 View

Problem with shRNA transfection. Why are only two plates getting contaminated instead of all?

I transfected my LNCaP-WT cells with 3 shRNA plus their NTC two weeks ago and split two puromycin selected cell plates on Friday last week(Feb 26). I checked for GFP in the cells, and they all...

28 February 2021 4,949 3 View

PUC19 as a transfer plasmid for lentiviral delivery?

Hello, Is it possible to use pUC19 as a transfer vector to be packed in using the second generation viral particles packaging system( pMD2.G; psPAX2 plasmids)? As far as I understand it there is...

28 February 2021 4,868 2 View

Did anyone ever try using pLVX-TetOne Plasmid with a copGFP as a selection marker instead of Puromycin?

When using a lentiviral vector for inducible expression of genes using the Tet-On system. In the literature, I saw a widely used of pLVX-TetOne-Puro Plasmid, is there a reason why people prefer to...

25 February 2021 1,011 3 View

Why do the PCR bands from the cDNA templates (extraction from the cell after transfection) show different size from the band of the plasmid template?

After transfection with the plasmid ( linearized ) and subcloning of the cell lines, RNA was extracted from the cell and then reverse transcripted to cDNA. When PCR reactions were run to verify...

25 February 2021 5,712 3 View

How do I transfect a large plasmid into PC12 cells with nerve growth factor (NGF) receptor?

I have a large 16 kb plasmid, which I need to transfect into PC12 cells. Lipofectamin 2000 didn't work and with GFP alone the transfection rate is very low. I also tried the neon invitrogen...

25 February 2021 6,635 5 View