GREENER principles for environmentally sustainable computational science.

The carbon footprint of scientific computing is substantial, but environmentally sustainable computational science (ESCS) is a nascent field with many opportunities to thrive. To realize the immense green opportunities and continued, yet sustainable, growth of computer science, we must take a coordinated approach to our current challenges, including greater awareness and transparency, improved estimation and wider reporting of environmental impacts. Here, we present a snapshot of where ESCS stands today and introduce the GREENER set of principles, as well as guidance for best practices moving forward.

Role of residues in the tryptophan repeat motif for HIV-1 reverse transcriptase dimerization.

The tryptophan repeat motif of the human immunodeficiency virus type-1 (HIV-1) reverse transcriptase (RT) is comprised of a cluster of six tryptophan residues at codons 398, 401, 402, 406, 410 and 414 that are highly conserved amongst primate lentiviral RTs. To determine the contributions of each of these residues for HIV-1 RT dimerization, we introduced changes into cloned DNA and tested the mutant subunits for their capacity to mediate heterodimerization in the yeast two-hybrid system. Changes of residue 401 to either leucine or alanine (but not phenylalanine) and residue 414 to leucine resulted in major reductions in beta-galactosidase activity produced from the reporter gene as compared to yeast expressing wild-type p66 bait and p51 prey fusions.