Search found 37 matches

by snowcapk
Tue May 13, 2008 3:56 am
Forum: Molecular Biology
Topic: Cleaning DNA from test tube
Replies: 4
Views: 2882

Since it's a maxiprep, I don't think the OP wants to degrade the DNA, but rather to collect it. I have had this problem before. If it's a large construct like a BAC that you are purifying, *do not vortex* to resuspend. Try heating the solution at ~37C for 20 min. This should cause the DNA to resuspe...
by snowcapk
Sat May 10, 2008 8:35 pm
Forum: Cell Biology
Topic: vehicle treated apoptosis
Replies: 3
Views: 3325

Just plain water? Maybe osmotic shock.
by snowcapk
Fri May 09, 2008 4:49 am
Forum: Cell Biology
Topic: submetacentric chromosome -- P and Q arms
Replies: 1
Views: 2880

p is for petit(e)...
by snowcapk
Fri May 09, 2008 4:47 am
Forum: Cell Biology
Topic: interpreting a TEM
Replies: 6
Views: 4386

White circles = high transmission, so my guess is they are vacuoles or vesicles inside a more electron-dense cell. Mutations in the secretory pathway can cause accumulation of these vesicles (see page three of this pdf).
by snowcapk
Tue May 06, 2008 10:04 am
Forum: Cell Biology
Topic: Webbed toes
Replies: 3
Views: 7130

People with webbed toes don't have a general deficit in apoptosis: their brains would explode out of their heads long before they got old enough to develop cancer. You've probably seen those pictures of caspase-9 KO embryos. I agree with MrMistery that the defect is probably downstream of a particul...
by snowcapk
Fri May 02, 2008 5:48 pm
Forum: Molecular Biology
Topic: inactive enzyme after purification with Ni-TED
Replies: 3
Views: 4535

I found an abstract where they use Tris to inactivate a Mn-containing protein by removing the bound manganese. The wash and elution buffers you used to purify the protein probably contain Tris, although likely in lower concentrations - check the manual if possible. In this paper in which Mn-SOD was ...
by snowcapk
Fri May 02, 2008 3:51 am
Forum: Molecular Biology
Topic: 6X His Tag vector construction assistance needed
Replies: 2
Views: 8129

I think it depends. If you are using Qiagen's NI-NTA system (or some other nickel or cobalt-based system) to purify the His-tagged protein, it shouldn't matter for that step whether there are a few extra aas at the N terminus before the 6xHis tag. However, you may have a problem if you try to remove...
by snowcapk
Wed Apr 23, 2008 12:39 am
Forum: Molecular Biology
Topic: Streaked DNA
Replies: 5
Views: 3962

Streaking can also refer to the phenomenon of sample migrating more slowly along the edges of the lanes. In this gel , you can see in lanes 3 and 4, for example, how the band is "U"-shaped instead of "-"-shaped. (I have seen much worse, but this is what came up on google images.)...
by snowcapk
Tue Apr 22, 2008 9:13 pm
Forum: Molecular Biology
Topic: DNA translation for publication
Replies: 3
Views: 3717

Hi Iruka, A figure like the one you've described consumes a lot of space. Make one if you like, but the publisher may well ask you to remove it or place it in the SOM. Journals like Science are on a mission to save space: they don't even let you include article titles in your references section. Mos...
by snowcapk
Mon Apr 21, 2008 6:28 pm
Forum: Molecular Biology
Topic: 1 MOLAR histidine?
Replies: 6
Views: 6825

See, to me, this would suggest that the histidine/bicarb might be dissolved in DMSO. After all, your FNBT reagent is in DMSO. If nothing else, histidine/bicarb dissolved in DMSO would be miscible with your FNBT/1M bicarb solution, and because you are only adding 40uL to 400uL of existing solution, a...
by snowcapk
Mon Apr 21, 2008 3:01 am
Forum: Molecular Biology
Topic: 1 MOLAR histidine?
Replies: 6
Views: 6825

I don't have access to that paper so this is a complete shot in the dark...what solvent are you using? Are you sure it should be DMSO or water or whatever else you chose?
by snowcapk
Sun Apr 20, 2008 12:05 am
Forum: Molecular Biology
Topic: PCR
Replies: 3
Views: 2715

I pity the fool who is heterozygous for sheep prion protein...