...sequence. This means cloning occurs in vivo, as compared to restriction enzyme cloning where the genetic...homology to the target site for recombination. Key components of the Lambda Red recombineering system The lambda... lambda red recombineering system has three components (Figure 1): 1) Exo, 2) Beta, and 3) Gam. All three...dsDNA was short enough, a ssDNA whose entire complementary strand was degraded. Beta: Beta protects the...created by Exo and promotes its annealing to a complementary ssDNA target in the cell.  Only Beta expression...an ssDNA oligo substrate.   Figure 1: Components of the Lambda Red Recombineering system. See ...region of interest and design an oligo that is complementary to the lagging strand. In practice, it’s easier...

... of powdered media. Filtration does not ensure complete sterilization as mycoplasma can even escape 0.2... growth of mycoplasma but cannot eradicate it completely. When mycoplasmas are seen in the culture, it...mycoplasmas are used. A broad range of primers encompasses almost all the infecting mycoplasma. The primers...assay kits are available from different biotech companies which are enzyme-based mycoplasma detection kits...synthesized by eukaryotic cells. First, the kit components rupture the mycoplasma and then specific enzymes... of mycoplasma. These methods cannot guarantee complete removal of mycoplasma but, can get rid of most...Microbiol .44: 42–49  Uphoff Cc, Drexler Hg (2002) Comparative Antibiotic Eradication of Mycoplasma Infections...

...throughout your career. Plus, just one role can encompass many of these activities leading to a rich day-to-day...combat sexual harassment in academia or a large company who decides how they are going pursue regulatory...science policy roles exist. Explore these resources compiled by the AAAS Science and Technology Policy Fellowship...working in science policy doesn’t have to be a complete career pivot. There are many ways to pursue your...system? Defining your why is what will make you a competitive candidate for any science policy position and...expertise and then once selected, you can pivot to a completely new field without issue. This may be more challenging...much smoother.  Action Items:  Explore this comprehensive resource developed by Dr. Kelly Singel which...

... TF library (aka the MORF Collection) and an accompanying expression atlas, including over 3,500 human...from these sites. The Zhang lab generated a comprehensive library of each unique TF open reading frame...endoderm, and mesoderm). These profiles were then compared to that of reference cell types generated by the... the human fetal expression atlas. Computational analysis was used to infer differentiation trajectories...Previously engineered TF libraries were not as comprehensive as this one, so it is an invaluable tool to ...expression dysregulation event. Diseases are often complex, with multiple layers of dysregulation from either...

...that no component of the overall project gets left undone or is duplicated. With each component of the ...the project completed by an individual who is a local expert in that task (or has the bandwidth to become...result is high quality and the entire process is completed more efficiently. Listen to our podcast interview...desired outcomes. Concern yourself with what is accomplished, rather than detailing how the work should be...in more engaged, successful employees who can accomplish great things.   To read more on this topic and...

...track of computation work comes with new sets of challenges. One challenge with computational analyses... of biologists are finding themselves using computational approaches to analyze large data sets (myself...RNA-seq analysis. I had never interacted with a computer at the command line, and so was really starting...especially since you’ll want to dig in to the computation, but they will serve you well as you perform ...directory: A directory is a file system in the computer and is just another name for a folder. For instance...

...fluorescent proteins, how to do a head-to-head comparison of fluorescent proteins and how to make a well-informed...your selection on a small-scale head-to-head comparative study under conditions that best mimic the intended...protein properties and provides a quick way to compare fluorescent proteins, e.g. see Chudakov et al (...is of no use. Therefore, it is more sensible to compare fluorescent proteins based on their practical brightness...promising fluorescent proteins and to determine and compare their practical brightness in a system closely ...application. In figure 2 we provide an example of the comparison of the practical brightness of two orange fluorescent...

...expressed in cells, generates much less signal than comparable fluorescent proteins. This weak emission hasn... with increased sensitivity and faster imaging compared to previous publications. They also developed ...they successfully imaged multiple subcellular compartments over several minutes using Nano-lantern fusion... fluorescence, so higher concentrations of the compound can be added to the media. Cellular esterase then...producing a constant supply of substrate. Using this compound to excite the Nano-lanterns, Takai et al. continuously... handy. This approach is especially suited to complement optogenetic tools, where light used for excitation...

...all bacteria are naturally competent to take up DNA, they can be made competent through chemical manipulation...Addgene’s blog to learn about making your own competent cells and our protocols page to learn about bacterial... The phagemids are packaged into replication-incompetent phage particles with assistance from a ‘helper... A., and Karen Guillemin. "Multiple phases of competence occur during the Helicobacter pylori growth cycle...Meibom, Karin L., et al. "Chitin induces natural competence in Vibrio cholerae." Science 310.5755 (2005):...

...and reduce needed compensation.    Working with antibodies can get a bit complicated, but hopefully this...time-sensitive, using precious samples, or being compared to other data in a manner that demands high accuracy... reaction to understand if any of your buffer components could affect the reaction. For instance, sodium...detected in the same assay. This is one of the most complex subjects in antibody-based protocols - but thankfully...another channel's detection range. Though you can compensate for this when reading your data, you’ll want ...

...was contributed by guest blogger Alan Wong. The complexity of biological systems can hinder our attempts...simple tool that allowed us to rapidly decode the complexity? The CombiGEM-CRISPR technology was developed...of providing an easy-to-use tool to analyze the complex combinatorial genetic networks underlying your ...mapping the combinatorial genetics that underlie complex regulation in biological systems. The CombiGEM ...new technologies to interrogate and understand complex biological systems. He can be contacted at aslw...transcriptional activation by an engineered CRISPR-Cas9 complex." Nature (2014). PubMed PMID: 25494202. PubMed ...

...based on size. Whether higher molecular weight complexes are detected will depend on the homodimer affinity...During the experiment, the solution is diluted, complicating the interpretation. Because of this, these methods...fluorescent protein is monomeric without the accompanying data to prove it is worthless. The OSER assay...and biological properties of new fusions can be compared with mEGFP or mTurquoise2, which are established...that you will be using. If you do a head-to-head comparison right, it will be valuable information for the... are engineered can be shared to simplify the comparison by others. Together, we can build a valuable ...

...us to the key question: what is the best way to compare the photostability of different fluorescent proteins...measurements for different fluorescent proteins and by comparing how the fluorescence intensity changes over time...photostability of the fluorescent proteins can be directly compared. An example of a photostability measurement of...fluorescent protein can be identified by a head-to-head comparison of several fluorescent proteins of the same spectral.... In figure 1 we provide an example of such a comparison between cyan fluorescent proteins using widefield... power, the photostability of the variants is comparable (lower panel of figure 1). To avoid changes in...

...specific chromosome. This image represents the composite of fluorescent measurements from red, blue, and...modified GFP-dCas9 and the gRNA scaffold to enhance complex assembly, thereby decreasing the amount of background... labeling efficiency was similar to that of a comparable FISH method. Importantly, they did not observe...with the previously established physical map. In comparing pairs of targets ~2 Mbp apart, they noticed that...that they could evaluate the degree of chromatin compaction even for this small distance! To the authors’...CRISPRainbow generates 6 unique colors and a white composite. gRNAs with two identical hairpin binding domains...

.... Addgene is now as much a tech company as it is a reagent company. I used to have to worry about this...remarkably so for a 90 person company. We were and remain ahead of most companies in creating a welcoming, ...often focus on the excitement of what we are accomplishing and what more we might do. I am grateful every...innovative thinking, and openness to team work.   Company culture Once in awhile I worry a very little ...

...specific components that are key to the cloning reaction. Understanding the specific components is essential...take up your insert. But exactly how does ccdB accomplish this? Let’s start with a brief history of the...system contains ccdB. A successful insertion will completely replace ccdB with the investigator’s insert of...interest.   CcdB resistant E. coli strains complete the system But ccdB alone isn’t the only key to...protein involves poisoning of DNA-topoisomerase II complexes.” J Mol Biol. 1992 Aug 5;226(3):735-45. PubMed...

... and trolls. People don’t like to connect with complete strangers as it borders on my first rule of networking...’m asked a lot about requesting connections to complete strangers for informational interviews. Many have...option is in the “More…” menu. You can also follow companies and organizations to see their news and job postings...interviews.  Pro tip: You can learn a lot from the company LinkedIn page. This can include news, inclusion...It’s also a great way to keep track of past accomplishments. Follow all the rules of good resume writing...writing. Include examples of concrete accomplishments in both the technical and “plus skills” areas. Include...

...and the efficacy of your competent cells (when they get old, they lose competency). If all the above is ... be sure that the buffers and temperature are compatible between the different enzymes. Always check the...source (i.e. primer3) or provided by the major companies selling PCR reagents. Nowadays commercial polymerases...a general rule, try to use an excess of insert compared to the backbone plasmid; a starting point could...plasmid. Many vectors contain sequences that are complementary to standard sequencing primers. If not, design...

...presentation, lost in a sea of data, my mind went completely blank. After several seconds of truly panicked...honest, if my paper hadn’t been ridiculously more complex than the one before it, I don’t think I would have... panicked state, only option one would let me accomplish my goal.   As a scientist, public speaking isn't...dumpster noises were just last week!  Nerves It’s completely normal to be anxious, nervous, and/or apprehensive... in its most difficult form. You’re presenting complex data, to a group of peers who are there to provide...conferences, or even just provide quick updates during a company meeting increases visibility of your work, opens...

... do as genetic circuits become larger and more complex? Voigt: If you look at all the products of biology... on genes at different times. It requires more complex synthetic networks. Addgene: What hurdles did you... perspective and you can layer them for more complicated functions. Those things are easy with CRISPR..... There haven’t been enough genetic parts for complexity. We have characterized almost 600 terminators...of a cell. The objective is to give people the complete toolbox for taking on very large genetic engineering...just using what biology has given us. Wood is a complicated material and we can access it, but we are stuck...