The pattern and extent of DNA methylation can significantly affect the success of restriction digestions
or bacterial transformations. Prokaryotic DNA may be methylated by host restriction/modification
systems, while eukaryotic DNA often is methylated i - [Read A practical guide to DNA methylation Promega PDF]
Accumulation of lipophilic substances in the plasma membrane may affect the membrane lipid order and consequently affect the function of these proteins. Changes in the activity of the Na+/K+ -ATPase, which is the major active transport system responsible for the electrochemical potential in mammalian cells, can therefore be an indication of the effect that a chemical may have on the viability of the cell membrane and possibly the whole cell. - [Read Hamster Ovary Cell NA+/K+ -ATPase Test]
In this protocol, bacterial cells are lysed by being subjected to short, intense treatments with ultrasound, which breaks the cell walls and shears the DNA into sizes that will not affect the viscosity of the samples. Note that this method causes some denaturation of the samples. The resulting lysate is ready for preclearing. - [Read Immunoprecipitation: Lysing Bacteria by Sonication Protocol]
Protocol describes transfection of plasmid DNA into mammaliancell lines using electroporation, a process whereby externalapplication of electric pulses induce cell membrane permeability.A number of factors can affect electrotransfection efficiency.In general, cells in suspension and small volume cells are difficultto transfect, whereas adherent cells and large volume cellsare relatively easy. - [Read Optimizing Electrotransfection of Mammalian Cells In Vitro Protocol]
Quality Control Considerations for Cell Culture- http://www.sigmaaldrich.com/Area_of_Interest/Life_Science/Cell_Culture/Key_Resources/ECACC_Handbook/Cell_Culture_Techniques_9.html#Quality%2520Control
Quality is important in all aspects of tissue culture since the quality of materials used i.e. media and other reagents) will affect the quality of the cultures and products derived from them. The main areas of quality control that are of concern for tissue culture are: The quality of the reagents and materials; The provenance and integrity of the cell lines; The avoidance of microbial contamination. - [Read Quality Control Considerations for Cell Culture]
Quantitation of Rare DNAs by PCR Protocol- https://catalog.invitrogen.com/index.cfm?fuseaction=iProtocol.unitSectionTree&treeNodeID=3DD0EEF8E2C50E5631409DE1B105D749&objectid=6676A8D899C49A6D38160C5130F2C612
Protocol that uses the polymerase chain reaction (PCR) to quantitate the numbers of a particular DNA sequence, from 1 to 20,000 molecules per sample. In addition, it helps assess the presence of contaminating sequences, which can seriously affect the outcome of the procedure. - [Read Quantitation of Rare DNAs by PCR Protocol]
No cell culture problem is as universal as that of culture loss due to contamination. All cell culture laboratories and cell culture workers have experienced it. Culture contaminants may be biological or chemical, seen or unseen, destructive or seemingly benign, but in all cases they adversely affect
both the use of your cell cultures and the quality of your research. Contamination problems can be divided into three classes: Minor annoyances, Serious problems, Major catastrophes. - [Read Understanding and Managing Cell Culture Contamination Protocol]
The protocol gives general considerations for the design of targeting vectors for transgenic mice. The protocol shares tips in the design of knock-out and knock-in vectors and some of their strategies for producing homologously recombined embryonic stem cells.