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Summary Proteins carry out life's essential functions. Comprehensive proteome analysis technologies are thus required for a full understanding of the operating principles of biological systems. While current proteomics techniques suffer from limitations in sensitivity and/or throughput, nanopore technology has the potential to enable de novo protein identification through single-molecule sequencing. However, a significant barrier to achieving this goal is controlling protein/peptide translocation through the nanopore sensor for processive strand analysis. Here, we review recent approaches that use a range of techniques, from oligonucleotide conjugation to molecular motors, aimed at driving protein strands and peptides through protein nanopores. We further discuss site-specific protein conjugation chemistry that could be combined with these translocation approaches as future directions to achieve single-molecule protein detection and sequencing of native proteins.

Genetically encoded reporter proteins are a cornerstone of molecular biology. While they are widely used to measure many biological activities, the current number of uniquely addressable reporters that can be used together for one-pot multiplexed tracking is small due to overlapping detection channels such as fluorescence. To address this, we built an expanded library of orthogonally-barcoded Nanopore-addressable protein Tags Engineered as Reporters (NanoporeTERs), which can be read and demuxed by nanopore sensors at the single-molecule level. By adapting a commercially available nanopore sensor array platform typically used for real-time DNA and RNA sequencing (Oxford Nanopore Technologies’ MinION), we show direct detection of NanoporeTER expression levels from unprocessed bacterial culture with no specialized sample preparation. These results lay the foundations for a new class of reporter proteins to enable multiplexed, real-time tracking of gene expression with nascent nanopore sensor technology.

Many factors influence the problems that currently exist in the learning-teaching process of programming. The use of an Integrated Development Environment (IDE) makes the experience a complicated process because these IDEs focus on professional programmers and not on novice learners. This also affects the classrooms of the university “Pontificia Universidad Católica de Valparaíso (PUCV)” (Chile). The use of professional IDEs negatively affects the learning process of first-year students who face the development of the algorithms for the first time. One of the IDE widely used for teaching programming courses is Code::Blocks, which is a tool for professional developers. Through a heuristic and usability evaluation, we found that Code::Blocks has a complex user interface and a functional overload. Using these two findings, as well as recommendations given during these tests, we highlight the important aspects that an IDE for novice learners should have. Taking into account previous observations and state-of-the-art/practice of IDEs, a functional IDE prototype, named Incre-IDLE, is developed. In addition to Code::Blocks evaluations, this paper reports the results of a heuristic and usability evaluation applied to first-year students at PUCV about functionalities provided by Incre-IDLE. These results suggest that Incre-IDLE has a simple interface, is easy to install and use, and does not have functional overload (i.e., spend a considerable amount of time learning the tool). Concretely, the results show that 66.7% of the students could complete tasks easily and 100% of them found the GUI intuitive. In terms of GUI, 83.3% considered the application interface “very simple”; and the text, concepts, and icons “very understandable” by 66.7%. The students also found the tool “motivating” (66.7%) or “very motivating” (33.3%). These results closely match the findings obtained by the heuristic evaluation of Incre-IDLE from the experts: 83.3% of them rated it as “useful” or “very useful”, and only a 16.7% rated it as “useless”.