Louis Pasteur and the birth of microbiology in Denmark.

Høiby N. Louis Pasteur and the birth of microbiology in Denmark. APMIS 2022. Louis Pasteur's work initiated the birth of microbiology in Denmark. Carl Julius Salomonsen was the pioneer who inspired and taught Christian Gram, Thorvald Madsen and Bernhard Bang bacteriological techniques in his annual bacteriological course which he started in 1883 at the University of Copenhagen. These pioneers developed Danish human and veterinary microbiology and became world famous. Emil Chr. Hansen developed Danish technical/industrial microbiology in the Carlsberg Laboratory and purified yeast and designed equipment for the propagation of pure yeast which was used worldwide in beer brewing. He also became world famous. The fascinating birth and development of Danish microbiology is summarized in this article, which is dedicated to the 200th birthday of Louis Pasteur, December 27, and 100th birthday of the Danish Pasteur Society, October 25, 2022.

International Microorganism Day: facilitating global outreach events using a decentralized model.

On 17 September 1683, Antonie van Leeuwenhoek, a Dutch merchant who lacked formal education and fortune, wrote a letter to the Royal Society of London describing for the first time a single-celled organism. As a tribute to this revolutionary discovery, the Portuguese Society of Microbiology with the support of the Federation of European Microbiological Societies in 2017, designated this day as International Microorganism Day (IMD), a day aiming to raise awareness about the wonderful world of microbes. Six years after the establishment of IMD, the knowledge of microbiology outreach around this celebration has expanded greatly, with 5 years of in-person and 2 years of online events. The peak of these commemorations was in 2023, with 63 parallel outreach events and more than 5000 attendees, most of which were children, and young adults. While these in-person events were occurring in the month of September, the #InternationalMicroorganismDay hashtag reached nearly 2.3 million people online, reflecting the number of users who have seen a post containing this hashtag on social media. Using a decentralized model to facilitate 63 grass-roots teams to organize events locally, IMD achieved global representation both online and offline. This paper presents details behind the organization and data on the international impact of the IMD 2022 and 2023 events, outlines plans to expand reach to more countries and audiences, and encourages readers to participate with their own events in future IMD editions so that global impact can be expanded even further.

Unraveling the functional dark matter through global metagenomics.

Metagenomes encode an enormous diversity of proteins, reflecting a multiplicity of functions and activities1,2. Exploration of this vast sequence space has been limited to a comparative analysis against reference microbial genomes and protein families derived from those genomes. Here, to examine the scale of yet untapped functional diversity beyond what is currently possible through the lens of reference genomes, we develop a computational approach to generate reference-free protein families from the sequence space in metagenomes. We analyse 26,931 metagenomes and identify 1.17 billion protein sequences longer than 35 amino acids with no similarity to any sequences from 102,491 reference genomes or the Pfam database3. Using massively parallel graph-based clustering, we group these proteins into 106,198 novel sequence clusters with more than 100 members, doubling the number of protein families obtained from the reference genomes clustered using the same approach. We annotate these families on the basis of their taxonomic, habitat, geographical and gene neighbourhood distributions and, where sufficient sequence diversity is available, predict protein three-dimensional models, revealing novel structures. Overall, our results uncover an enormously diverse functional space, highlighting the importance of further exploring the microbial functional dark matter.

Antoni van Leeuwenhoek 1723-2023: a review to commemorate Van Leeuwenhoek's death, 300 years ago : For submission to Antonie van Leeuwenhoek journal of microbiology.

In the 300 years since Van Leeuwenhoek died, some of the details around his life and his work have provided material for discussion or dispute. As archives and libraries are being scanned and technology improves, information is becoming more readily available. This review therefore aims to take a new look at some of those discussions, and Van Leeuwenhoek's possible experimental methods. Digital photography has made it possible to show exactly what can be seen through his simple microscopes, and how he could have obtained his results by, for example, modifying his microscopes and lighting. Equally, the completion of the series known as the Collected Letters, begun in 1931 with volume 1 published in 1939 and to be completed in 2023, allows researchers to see complete letters in English and modern Dutch. Theories about experimental methods can be tested and the results recorded photographically. Additionally, new, non-destructive techniques such as neutron tomography have improved the evaluation of the authenticity of surviving microscopes.

Real-Lab-Day: undergraduate scientific hands-on activity as an authentic learning opportunity in microbiology education.

Traditional lab classes in microbiology are common in several educational institutions, which can provide a learning experience disconnected from the myriad of experiments performed in research laboratories. Attempting to promote an authentic learning opportunity of the functioning of a bacteriology research laboratory, we developed the "Real-Lab-Day," a multimodal learning experience to develop competencies, abilities, critical analysis, and teamwork skills for undergraduate students. Students were divided into groups and assigned to research laboratories to be mentored by graduate students, to design and carry out scientific assays. Undergraduate students were introduced to methods such as cellular and molecular assays, flow cytometry, and fluorescence microscopy, as tools to address scientific questions about bacterial pathogenicity, bacterial resistance, and other topics. To consolidate their learning, students created and presented a poster in a rotational panel of peer learning. The perceived learning and interest in microbiology research were improved by the Real-Lab-Day experience, and >95% of the students approved the Real-Lab-Day as a teaching tool in microbiology. Students exposed to a research laboratory had a positive experience with the teaching method, and over 90% saw it as beneficial to improve their understanding of the scientific concepts discussed during lectures. Likewise, their interest in pursuing a career in microbiology was stimulated by the Real-Lab-Day experience. In conclusion, this educational initiative depicts an alternative methodology to connect students to the research and offers an opportunity to be in close contact with experts and graduate students, who gain teaching experience.