A Gram-negative, rod-shaped bacterium commonly found in the lower intestines of warm-blooded animals.
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E. coli, risk of infection?
There has been a warning about E. coli contaminated water in South Florida. Now I'm wondering are there empirical data or historic cases which show a correlation between E.coli levels in tap water and ...
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1answer
46 views
Whence fecal E. coli (et al.) if swallowing it is dangerous?
I don't know much about medicine, and I know even less about microbiology, but I understand that there are organisms in the lower gastrointestinal tract (and in feces) of a human, like Escherichia ...
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0answers
29 views
What would cause E. coli to change from filamentous growth to normal growth?
In my lab we've observed a phenomenon in which a culture of E. coli is found to shift from normal rod growth to filamentous growth and then back to normal rod growth again several times over the ...
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56 views
Growth kinetics of E.coli on media containing lactose and casein
I did this experiment last month using E.coli isolated from raw milk and have following data via uv-spec:
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1answer
31 views
What is the extent of the effect of Tris on E. coli?
I was a fool and dissolved my antibiotic (Kanamycin) into Tris Buffer rather than H2O. The Kanamycin still seems to be active but a fellow labmate mentioned that Tris messes around with the membrane ...
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1answer
145 views
How useful are vitamin and trace element additions in E. coli culture medium?
In protocols for minimal media for growing bacteria I often see that a vitamin mix or a mix of various trace metals is added. But at least for E. coli I know that those are not strictly necessary, ...
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1answer
39 views
Salvaging a plasmid from a cell culture stored at the incorrect temperature
I have E. coli with transformed plasmid on agar in a vial. It has been stored at -20 degree C without glycerol stock for 18 hours.
This is a continuation of: Survival of E. coli on agar plate at -20 ...
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2answers
174 views
Survival of E. coli on agar plate at -20 degree C without glycerol stock
If I kept E. coli transformed with plasmid at -20˚C without making glycerol stock, will it survive? Actually I have kept it this way for 18 hours. What will happen with it? Will it grow in fresh ...
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3answers
249 views
Why is it sometimes difficult to resuspend E. coli in P1?
It's a curiosity question. When I'm doing minipreps after pelleting the bacteria sometimes it's very easy to resuspend them in P1 (Qiagen kit), but sometimes they form a rubbery clump that is very ...
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43 views
Literature about putative epigenetic state changes in mammal sequences after cloning steps in Escherichia coli
I would like you to point me out some literature about putative epigenetic state changes in mouse/mammal sequences after cloning steps in Escherichia coli.
This are the last search details I used in ...
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2answers
517 views
What is the appropriate method to send a strain?
We are planning to send an ecoli strain to another lab. What is the appropriate way to do so. No MTA is required but the options seem to be using filter paper or sending a glycerol stock on dry ice.
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139 views
What makes E. coli yellowish?
LB, TB media, and yeast extract are also yellow but at the heart of the question. What chemical(s) make E. coli yellow?
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3answers
104 views
Measuring reverse transcriptase activity in E. coli
Goal: To quantify the HIV-1 reverse transcriptase (RT) activity for a number of mutated RTs.
Idea:
Put RT into a vector in E.coli.
Deliver GFP mRNA to E.coli.
RT will process the mRNA.
The ...
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1answer
185 views
How long does it take for E. coli to shift feedstocks?
With our fermentations we're noticing that it takes an appreciable amount of time for E. coli (K12 variant) to change from being metabolically streamlined on amino acids to being metabolically ...
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3answers
1k views
How long can E. coli stocks be stored at -20°C?
I'm volunteering for a biohacker lab - biocurious in Sunnyvale. The have a pretty good set of equipment - gel boxes, incubators, but they don't have a -80°C freezer yet.
I'd like to set up some ...
6
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1answer
109 views
Which cryogenic vials and caps are ideal for storing glycerol stocks?
There are internally threaded, externally threaded, natural caps. For the vials, there are skirts, star-footed, and various bottoms. Why do any of these things matter?
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1answer
269 views
How do you knockout an E. coli gene without disrupting the rest of the gene cluster?
I'm familiar with the method to build Keio collection using single-gene deletion with an antibiotic cassette. However, what happens when there are gene clusters or overlapping ORFs and you still only ...
