We developed a new biological cloning system for HIV-1 isolates using the U87.CD4 cell lines that express different chemokine receptors. We demonstrate that our method is sensitive and specific because the clones isolated had the same coreceptor usage and genotype as viruses of the primary isolate. We evaluated our cloning system by isolating 27 biological clones from two primary HIV-1 R3R5X4 i...

The design and generation of DNA constructs is among the necessary but generally tedious tasks for molecular biologists and, typically, the cloning strategy is restricted by available restriction sites. However, increasingly sophisticated experiments require increasingly complex DNA constructs, with an intricacy that exceeds what is achievable using standard cloning procedures. Many transgenes ...

Precise DNA manipulation is a key enabling technology for synthetic biology. Approaches based on restriction digestion are often limited by the presence of certain restriction enzyme recognition sites. Recent development of restriction-free cloning approaches has greatly enhanced the flexibility and speed of molecular cloning. Most restriction-free cloning methods focus on DNA assembly. Much le...