Comparative electrophoretic study on ribosomal proteins from algae

Plant cytoplasmic ribosomal proteins: an update on classification, nomenclature, evolution and resources

Standardized naming systems are essential to integrate and unify distinct research fields, and to link multi-species data within and across kingdoms. We conducted a comprehensive survey of cytoplasmic ribosomal proteins (CRPs) in the dicot model Arabidopsis thaliana and the monocot model rice, noting that the standardized naming system has not been widely adopted in the plant community. We generated a database linking the old classical names to their updated and compliant names. We also explored the sequences, molecular evolution, and structural and functional characteristics of all plant CRP families, emphasizing evolutionarily conserved and plant-specific features through cross-kingdom comparisons. Unlike fungal CRP paralogs that were mainly created by whole-genome duplication (WGD) or retroposition under a concerted evolution mode, plant CRP genes evolved primarily through both WGD and tandem duplications in a rapid birth-and-death process. We also provide a web-based resource (http://www.plantcrp.cn/) with the aim of sharing the latest knowledge on plant CRPs and facilitating the continued development of a standardized framework across the entire community.

Phylogenetic position of some Chlorella species within the chlorococcales based upon complete small-subunit ribosomal RNA sequences

Complete small-subunit rRNA (16S-like rRNA) coding region sequences were determined for eight species of the Chlorococcales (Chlorophyceae). The genera investigated include Prototheca, Ankistrodesmus, Scenedesmus, and five Chlorella species. Distance matrix methods were used to infer a phylogenetic tree that describes evolutionary relationships between several plant and green algal groups. The tree exhibits a bifurcation within the Chlorococcales consistent with the division into Oocystaceae and Scenedesmaceae, but three of the five Chlorella species are more similar to other algae than to Chlorella vulgaris. All of the sequences contain primary and secondary structural features that are characteristic of 16S-like rRNAs of chlorophytes and higher plants. Anikstrodesmus stipitatus, however, contains a 394-bp group I intervening sequence in its 16S-like rRNA coding region.

Comparison of ribosomes and ribosomal proteins of sensitive and resistant mycobacteria

Ribosomal proteins from Mycobacterium tuberculosis H37 Rv were analyzed by polyacrylamide gel electrophoresis and 73 proteins were separated. The 30S subunit consists of 26 proteins, the 50S subunit of 41 proteins, 6 proteins of the ribosomes could not be shown in the subunits. The molecular weights for the proteins of the 30S subunit are 9100-43500, and for the proteins of the 50S subunit 8000-46000. The sedimentation coefficient have values of 28.8S and 47.7S. It was demonstrated that streptomycin-resistant cells in comparison to sensitive cells have two additional 30S proteins. Moreover, the protein L34 has changed its position. Kanamycin- and capreomycin-resistant cells have also two additional proteins, but viomycin shows no changes.