ABSTRACT
The bacteriophage population is vast, dynamic, old, and genetically diverse. The genomics of phages that infect bacterial hosts in the phylum Actinobacteria show them to not only be diverse but also pervasively mosaic, and replete with genes of unknown function. To further explore this broad group of bacteriophages, we describe here the isolation and genomic characterization of 116 phages that infect Microbacterium spp. Most of the phages are lytic, and can be grouped into twelve clusters according to their overall relatedness; seven of the phages are singletons with no close relatives. Genome sizes vary from 17.3 kbp to 97.7 kbp, and their G+C% content ranges from 51.4% to 71.4%, compared to ~67% for their Microbacterium hosts. The phages were isolated on five different Microbacterium species, but typically do not efficiently infect strains beyond the one on which they were isolated. These Microbacterium phages contain many novel features, including very large viral genes (13.5 kbp) and unusual fusions of structural proteins, including a fusion of VIP2 toxin and a MuF-like protein into a single gene. These phages and their genetic components such as integration systems, recombineering tools, and phage-mediated delivery systems, will be useful resources for advancing Microbacterium genetics.
Subject(s)
Actinobacteria/virology , Bacteriophages/genetics , Genetic Variation , Genome, Viral , Bacteriophages/classification , Bacteriophages/isolation & purification , Base Composition , DNA, Viral/genetics , Genes, Viral , Genomics , Phylogeny , Viral Fusion Proteins/geneticsABSTRACT
Triadic alignment is a pedagogical technique that instructors can use to improve their teaching and students' learning. It involves offering the course learning objectives, teaching and learning activities, and assessments at the same cognitive process level. Though it represents a best practice, few instructors have assessed the efficacy of triadic alignment. Previous research has demonstrated that General Biology courses are commonly misaligned relative to the objectives and assessments. However, little emphasis has been placed on assessing the teaching and learning activities as the third component of triadic alignment. In this article, we describe how a General Biology course was initially misaligned, the process that was taken to align it, and the improved student outcomes that resulted from triadic alignment. We expand our discussion to include types of misalignment and the benefits of triadic alignment for both the students and the faculty member.
