Rob Knight

Bio: Rob Knight is an academic researcher from University of California, San Diego. The author has contributed to research in topics: Microbiome & Gut flora. The author has an hindex of 201, co-authored 1061 publications receiving 253207 citations. Previous affiliations of Rob Knight include Anschutz Medical Campus & University of Sydney.

Feasibility of SARS-CoV-2 virus detection from consumer-grade cotton swabs

Abstract: To control the growing COVID-19 pandemic, increased testing and containment is essential, yet clinical-grade sampling supplies are expensive and rapidly being depleted. We demonstrate the feasibility of using alternative consumer-grade swabs stored in 95% ethanol rather than viral transport media to detect SARS-CoV-2 from ten hospitalized persons and hospital rooms.

Reply to: Examining microbe-metabolite correlations by linear methods

Abstract: Author(s): Morton, James T; McDonald, Daniel; Aksenov, Alexander A; Nothias, Louis Felix; Foulds, James R; Quinn, Robert A; Badri, Michelle H; Swenson, Tami L; Van Goethem, Marc W; Northen, Trent R; Vazquez-Baeza, Yoshiki; Wang, Mingxun; Bokulich, Nicholas A; Watters, Aaron; Song, Se Jin; Bonneau, Richard; Dorrestein, Pieter C; Knight, Rob

SARS-CoV-2 Infection Among Symptom-Free Healthcare Workers

Abstract: Importance: Current evidence suggests that transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is possible among symptom-free individuals but limited data are available on this topic in healthcare workers (HCW). The quality and acceptability of self-collected nasopharyngeal swabs (NPS) is unknown. Objective: To estimate the prevalence of SARS-CoV-2 infection and to assess the acceptability of self-collected NPS among HCW. Design: Cross-sectional convenience sample enrolled between April 20th and June 24th, 2020. We had >95% power to detect at least one positive test if the true underlying prevalence of SARS-CoV2 was > 1%. Setting: The metropolitan area surrounding Minneapolis and St. Paul, Minnesota. Participants: HCW free of self-reported upper respiratory symptoms were recruited. Exposures: Participants completed questionnaires regarding demographics, household characteristics, personal protective equipment (PPE) utilization and comorbidities. Outcomes: A participant self-collected nasopharyngeal swab (NPS) was obtained. SARS-CoV-2 infection was assessed via polymerase chain reaction. NPS discomfort was assessed on a scale of 1 (no discomfort) - 10 (extreme discomfort). NPS duration and depth into the nasopharynx, and willingness to perform future self-collections were assessed. Results: Among n=489 participants 80% were female and mean age+/-SD was 41+/-11. Participants reported being physicians (14%), nurse practitioners (8%), physicians assistants (4%), nurses (51%), medics (3%), or other which predominantly included laboratory technicians and administrative roles (22%). Exposure to a known/suspected COVID-19 case in the 14 days prior to enrollment was reported in 40% of participants. SARS-CoV-2 was not detected in any participant. The mean+/-SD discomfort level of the NPS was 4.5+/-2.0. 95% of participants reported that their self-swab was longer than or equal to the duration of patient swabs they had previously performed, and 89% reported the depth to be deeper than or equal to the depth of previous patient swabs. Over 95% of participants reported a willingness to repeat a self-collected NP swab in the future. Conclusions and Relevance: The point prevalence of SARS-CoV-2 infection was likely very low in symptom-free Minnesota healthcare workers from April 20th and June 24th, 2020. Self-collected NP swabs are well-tolerated and a viable alternative to provider-collected swabs to preserve PPE.

QIIME allows analysis of high-throughput community sequencing data.

Abstract: Supplementary Figure 1 Overview of the analysis pipeline. Supplementary Table 1 Details of conventionally raised and conventionalized mouse samples. Supplementary Discussion Expanded discussion of QIIME analyses presented in the main text; Sequencing of 16S rRNA gene amplicons; QIIME analysis notes; Expanded Figure 1 legend; Links to raw data and processed output from the runs with and without denoising.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

The SILVA ribosomal RNA gene database project: improved data processing and web-based tools

Abstract: SILVA (from Latin silva, forest, http://www.arb-silva.de) is a comprehensive web resource for up to date, quality-controlled databases of aligned ribosomal RNA (rRNA) gene sequences from the Bacteria, Archaea and Eukaryota domains and supplementary online services. The referred database release 111 (July 2012) contains 3 194 778 small subunit and 288 717 large subunit rRNA gene sequences. Since the initial description of the project, substantial new features have been introduced, including advanced quality control procedures, an improved rRNA gene aligner, online tools for probe and primer evaluation and optimized browsing, searching and downloading on the website. Furthermore, the extensively curated SILVA taxonomy and the new non-redundant SILVA datasets provide an ideal reference for high-throughput classification of data from next-generation sequencing approaches.

Introducing mothur: Open-Source, Platform-Independent, Community-Supported Software for Describing and Comparing Microbial Communities

Abstract: mothur aims to be a comprehensive software package that allows users to use a single piece of software to analyze community sequence data. It builds upon previous tools to provide a flexible and powerful software package for analyzing sequencing data. As a case study, we used mothur to trim, screen, and align sequences; calculate distances; assign sequences to operational taxonomic units; and describe the alpha and beta diversity of eight marine samples previously characterized by pyrosequencing of 16S rRNA gene fragments. This analysis of more than 222,000 sequences was completed in less than 2 h with a laptop computer.

Search and clustering orders of magnitude faster than BLAST

Abstract: Motivation: Biological sequence data is accumulating rapidly, motivating the development of improved high-throughput methods for sequence classification. Results: UBLAST and USEARCH are new algorithms enabling sensitive local and global search of large sequence databases at exceptionally high speeds. They are often orders of magnitude faster than BLAST in practical applications, though sensitivity to distant protein relationships is lower. UCLUST is a new clustering method that exploits USEARCH to assign sequences to clusters. UCLUST offers several advantages over the widely used program CD-HIT, including higher speed, lower memory use, improved sensitivity, clustering at lower identities and classification of much larger datasets. Availability: Binaries are available at no charge for non-commercial use at http://www.drive5.com/usearch Contact: [email protected] Supplementary information:Supplementary data are available at Bioinformatics online.