We start the new year with a bang, or at least a new paper published. Bioinformatics put our paper (1) describing the software package CAFE online today (although it was accepted late last year). The CAFE package is a combination of Perl and R tools that can analyze data from paired transposon mutant sequencing experiments (2-4), generate fitness coefficients for each gene and condition, and perform appropriate statistical testing on these fitness coefficients. The paper is short, but shows that CAFE performs as good as the best competing tools (5-7) while being superior at controlling for false positives (you’ll have to dig into the supplement to find the data for that though).

Importantly, this is a collaborative effort by basically the entire research group from last spring: me, Haveela, Emil, Anna and our visiting student Adriana. A big thanks to all of you for working on this short but important paper! You can read the full paper here.

References

1. Abramova A, Osińska A, Kunche H, Burman E, Bengtsson-Palme J (2021) CAFE: A software suite for analysis of paired-sample transposon insertion sequencing data. Bioinformatics, advance article doi: 10.1093/bioinformatics/btaa1086
2. Chao,M.C. et al. (2016) The design and analysis of transposon insertion sequencing experiments. Nature reviews Microbiology, 14, 119–128.
3. van Opijnen,T. and Camilli,A. (2013) Transposon insertion sequencing: a new tool for systems-level analysis of microorganisms. Nature reviews Microbiology, 11, 435–442.
4. Goodman,A.L. et al. (2011) Identifying microbial fitness determinants by insertion sequencing using genome-wide transposon mutant libraries. Nature Protocols, 6, 1969–1980.
5. McCoy,K.M. et al. (2017) MAGenTA: a Galaxy implemented tool for complete Tn- Seq analysis and data visualization. Bioinformatics, 33, 2781– 2783.
6. Zhao,L. et al. (2017) TnseqDiff: identification of conditionally essential genes in transposon sequencing studies. BMC Bioinformatics, 18.
7. Zomer,A. et al. (2012) ESSENTIALS: Software for Rapid Analysis of High Throughput Transposon Insertion Sequencing Data. PLoS ONE, 7, e43012.

In the sixth episode of the Microbiology Lab Pod, recorded on December 17, the crew (Johan Bengtsson-Palme, Emil Burman, Haveela Kunche, Anna Abramova, Marcus Wenne, Sebastian Wettersten and Mahbuba Lubna Akter) talks about Haveela’s master thesis, virtual conferences and bring three Christmas themed papers.

The specific papers discussed in the pod (with approximate timings) are as follows:

• 13:00 – Fulcher, M.R., Bolton, M.L., Millican, M.D., et al., 2020. Broadening Participation in Scientific Conferences during the Era of Social Distancing. Trends in Microbiology. https://doi.org/10.1016/j.tim.2020.08.004
• 25:15 – de Clercq, N.C., Frissen, M.N., Levin, E., et al., 2019. The effect of having Christmas dinner with in-laws on gut microbiota composition. Human Microbiome Journal 13, 100058. https://doi.org/10.1016/j.humic.2019.100058
• 44:00 – Garcia-Lemos, A.M., Gobbi, A., et al., 2020. Under the Christmas Tree: Belowground Bacterial Associations With Abies nordmanniana Across Production Systems and Plant Development. Frontiers in Microbiology 11. https://doi.org/10.3389/fmicb.2020.00198
• 56:15 – Halverson, L.J., Clayton, M.K., Handelsman, J., 1993. Population biology of Bacillus cereus UW85 in the rhizosphere of field-grown soybeans. Soil Biology and Biochemistry 25, 485–493. https://doi.org/10.1016/0038-0717(93)90074-L
• 65:00 – Glendinning, L., Genç, B., Wallace, R.J., Watson, M., 2020. Metagenomic analysis of the cow, sheep, reindeer and red deer rumen. bioRxiv. https://doi.org/10.1101/2020.02.12.945139

The podcast was recorded on December 17, 2020. If you want to reach out to us with comments, suggestions or other feedback, please send an e-mail to podcast at microbiology dot se or contact @bengtssonpalme via Twitter. The music that can be heard on the pod is composed by Johan Bengtsson-Palme and is taken from the album Cafe Phonocratique.

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This is the fifth episode of the Microbiology Lab Pod and has been lying around on my computer almost finished for way too long. It was recorded on September 23, and the bigger-than-ever-before crew (Johan Bengtsson-Palme, Emil Burman, Haveela Kunche, Anna Abramova, Marcus Wenne, Sebastian Wettersten and Mahbuba Lubna Akter) is joined by Fanny Berglund to discuss computational discovery of novel resistance genes. We also discuss antibiotic resistance mechanisms, particularly in Pseudomonas aeruginosa.

The specific papers discussed in the pod (with approximate timings) are as follows:

• 5:30 – Berglund, F., Johnning, A., Larsson, D.G.J., Kristiansson, E., 2020. An updated phylogeny of the metallo-b-lactamases. Journal of Antimicrobial Chemotherapy 7. https://doi.org/10.1093/jac/dkaa392
• 5:45 – Berglund, F., Österlund, T., Boulund, F., Marathe, N.P., Larsson, D.G.J., Kristiansson, E., 2019. Identification and reconstruction of novel antibiotic resistance genes from metagenomes. Microbiome 7, 52. https://doi.org/10.1186/s40168-019-0670-1
• 6:00 – Berglund, F., Marathe, N.P., Österlund, T., Bengtsson-Palme, J., Kotsakis, S., Flach, C.-F., Larsson, D.G.J., Kristiansson, E., 2017. Identification of 76 novel B1 metallo-β-lactamases through large-scale screening of genomic and metagenomic data. Microbiome 5, i29. https://doi.org/10.1186/s40168-017-0353-8
• 6:15 – Boulund, F., Berglund, F., Flach, C.-F., Bengtsson-Palme, J., Marathe, N.P., Larsson, D.G.J., Kristiansson, E., 2017. Computational discovery and functional validation of novel fluoroquinolone resistance genes in public metagenomic data sets. BMC Genomics 18, 438. https://doi.org/10.1186/s12864-017-4064-0
• 37:15 – Crippen, C.S., Jr., M.J.R., Sanchez, S., Szymanski, C.M., 2020. Multidrug Resistant Acinetobacter Isolates Release Resistance Determinants Through Contact-Dependent Killing and Bacteriophage Lysis. Frontiers in Microbiology 11. https://doi.org/10.3389/fmicb.2020.01918
• 52:15 – Leonard, A.F.C., Zhang, L., Balfour, A.J., Garside, R., Hawkey, P.M., Murray, A.K., Ukoumunne, O.C., Gaze, W.H., 2018. Exposure to and colonisation by antibiotic-resistant E. coli in UK coastal water users: Environmental surveillance, exposure assessment, and epidemiological study (Beach Bum Survey). Environment International 114, 326–333. https://doi.org/10.1016/j.envint.2017.11.003
• 53:30 – Bengtsson-Palme, J., Kristiansson, E., Larsson, D.G.J., 2018. Environmental factors influencing the development and spread of antibiotic resistance. FEMS Microbiology Reviews 42, 25. https://doi.org/10.1093/femsre/fux053
• 54:30 – Leonard, A.F.C., Zhang, L., Balfour, A.J., Garside, R., Gaze, W.H., 2015. Human recreational exposure to antibiotic resistant bacteria in coastal bathing waters. Environment International 82, 92–100. https://doi.org/10.1016/j.envint.2015.02.013
• 55:30 – Ahmed, M.N., Abdelsamad, A., Wassermann, T., et al., 2020. The evolutionary trajectories of P. aeruginosa in biofilm and planktonic growth modes exposed to ciprofloxacin: beyond selection of antibiotic resistance. npj Biofilms and Microbiomes 6. https://doi.org/10.1038/s41522-020-00138-8
• 69:30 – Rezzoagli, C., Archetti, M., Mignot, I., Baumgartner, M., Kümmerli, R., 2020. Combining antibiotics with antivirulence compounds can have synergistic effects and reverse selection for antibiotic resistance in Pseudomonas aeruginosa. PLOS Biology 18, e3000805. https://doi.org/10.1371/journal.pbio.3000805
• 79:45 – Allen, R.C., Popat, R., Diggle, S.P., Brown, S.P., 2014. Targeting virulence: can we make evolution-proof drugs? Nature reviews Microbiology 12, 300–308. https://doi.org/10.1038/nrmicro3232
• 80:45 – Köhler, T., Perron, G.G., Buckling, A., van Delden, C., 2010. Quorum Sensing Inhibition Selects for Virulence and Cooperation in Pseudomonas aeruginosa. PLoS Pathogens 6, e1000883. https://doi.org/10.1371/journal.ppat.1000883

The podcast was recorded on September 23, 2020. If you want to reach out to us with comments, suggestions or other feedback, please send an e-mail to podcast at microbiology dot se or contact @bengtssonpalme via Twitter. The music that can be heard on the pod is composed by Johan Bengtsson-Palme and is taken from the album Cafe Phonocratique.

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This week, in a stroke of luck coinciding with my conference presentation on the same topic, my review paper on microbial model communities came out in Computational and Structural Biotechnology Journal. The paper (1) provides an overview of the existing microbial model communities that have been developed for different purposes and makes some recommendations on when to use what kind of community. I also make a deep-dive into community intrinsic-properties and how to capture and understand how microbes growing together interact in a way that is not predictable from how they grow in isolation.

The main take-home messages of the paper are that 1) there already exists a quite diverse range of microbial model communities – we probably don’t need a wealth of additional model systems, 2) there need to be better standardization and description of the exact protocols used – this is more important in multi-species communities than when species are grown in isolation, and 3) the researchers working with microbial model communities need to settle on a ‘gold standard’ set of model communities, as well as common definitions, terms and frameworks, or the complexity of the universe of model systems itself may throw a wrench into the research made using these model systems.

The paper was inspired by the work I did in Jo Handelsman‘s lab on the THOR model community (2), which I then have brought with me to the University of Gothenburg. In the lab, we are also setting up other model systems for microbial interactions, and in this process I thought it would be useful to make an overview of what is already out there. And that overview then became this review paper.

The paper is fully open-access, so there is really not much need to go into the details here. Go and read the entire thing instead (or just get baffled by Table 1, listing the communities that are already out there!)

References

1. Bengtsson-Palme J: Microbial model communities: To understand complexity, harness the power of simplicity. Computational and Structural Biotechnology Journal, in press (2020). doi: 10.1016/j.csbj.2020.11.043
2. Lozano GL, Bravo JI, Garavito Diago MF, Park HB, Hurley A, Peterson SB, Stabb EV, Crawford JM, Broderick NA, Handelsman J: Introducing THOR, a Model Microbiome for Genetic Dissection of Community Behavior. mBio, 10, 2, e02846-18 (2019). doi: 10.1128/mBio.02846-18

I am very happy to share the news that our starting grant application to the Swedish Research Council has been granted 3.3 million SEK of funding for four years! This is fantastic news, as it allows us to further explore the interactions between bacteria in the human microbiome that are important for community stability and resilience to being colonized by pathogens. In the granted project, we will investigate environmental and genetic factors that are important for bacterial invasiveness and community stability in the human gastrointestinal tract.

Within the scope of the project, we will establish model bacterial communities and experimental systems for the human stomach and intestine. We will then investigate how disturbances, such as antibiotic exposure, change the interactions in these microbial communities and their long-term stability. Finally, we aim to identify genes that contribute to successful bacterial colonization or resilience to invasion of established communities in the human microbiome.

Aside from myself, Prof. Sara Lindén and Dr. Kaisa Thorell from the University of Gothenburg as well as Prof. Ed Moore at the university’s Culture Collection will be involved in this project in different ways. We will also collaborate with my former postdoc supervisor Prof. Jo Handelsman as well as Dr. Ophelia Venturelli at the University of Wisconsin-Madison. Finally, we will also collaborate with Dr. Åsa Sjöling at the Karolinska Institute. I look forward to work with you all over the coming four years! A big thanks to the Swedish Research Council for believing in this research and investing in making it happen!

I am very happy to share the news that I have been awarded with the Gothenburg Society of Medicine and the Sahlgrenska Academy’s prize to young researchers for our research on the effects of antibiotics on bacteria, including, of course, antibiotic resistance.

I am incredibly honoured by being selected for this award. I am also thrilled with that the Gothenburg Society of Medicine, which is a society mostly for medical doctors, sees the value in our broad, one-health, take on antibiotic resistance as well as other effect that antibiotics may have on microbes, both in the human body and in the environment. The recognition of antibiotic resistance as a one-health problem with solutions both within and outside of the typical medical setting is instrumental for our ability to curb future resistance development.

The award ceremony will take place in connection with the Gothenburg Society of Medicine’s closing meeting on 2 December, where I will present our research together with the senior awardee Professor Claes Ohlsson, who is awarded for his groundbreaking research on osteoporosis.

For a bit more than a year, I have been part of an EFSA panel on biological hazards on cross contamination with antibiotic substances in animal feed. This week the panel has launched an open consultation on sections of the draft scientific opinion, including the proposed methodology and the data gaps identified. Anyone who are interested can submit written comments before 18 November 2020, and the full information can be found at the EFSA website.

The fall semester has begun, and with that we have started a new round of recordings of the Microbiology Lab Pod. Our fourth episode was recorded on August 20, and the now-familiar crew (Johan Bengtsson-Palme, Emil Burman, Haveela Kunche and Anna Abramova) has been augmented with two new master students in the lab: Sebastian Wettersten and Mahbuba Lubna Akter. This time, we discuss microbial communities of dead and alive deep-sea hydrothermal vents, look at a model system for pathogenic biofilm formation in the lungs, and check in on why patients with covid-19 commonly lose their sense of smell.

The specific papers discussed in the pod (with approximate timings) are as follows:

• 11:30 – Hou, J., Sievert, S.M., Wang, Y. et al., 2020. Microbial succession during the transition from active to inactive stages of deep-sea hydrothermal vent sulfide chimneys. Microbiome 8, 102. https://doi.org/10.1186/s40168-020-00851-8
• 28:45 – Harrington, N.E., Sweeney, E., Harrison, F., 2020. Building a better biofilm – Formation of in vivo-like biofilm structures by Pseudomonas aeruginosa in a porcine model of cystic fibrosis lung infection. Biofilm 2, 100024. https://doi.org/10.1016/j.bioflm.2020.100024
• 52:30 – Brann, D.H., Tsukahara, T., Weinreb, C., et al., 2020. Non-neuronal expression of SARS-CoV-2 entry genes in the olfactory system suggests mechanisms underlying COVID-19-associated anosmia. Science Advances 6, eabc5801. https://doi.org/10.1126/sciadv.abc5801
• 71:45 – Chen, M., Shen, W., Rowan, N.R., et al., 2020. Elevated ACE2 expression in the olfactory neuroepithelium: implications for anosmia and upper respiratory SARS-CoV-2 entry and replication. European Respiratory Journal 2001948. https://doi.org/10.1183/13993003.01948-2020
• 77:15 – Zhang, X., Wang, J., 2020. Deducing the Dose-response Relation for Coronaviruses from COVID-19, SARS and MERS Meta-analysis Results. medRxiv. https://doi.org/10.1101/2020.06.26.20140624
• 78:30 – Sekine, T., Perez-Potti, A., Rivera-Ballesteros, O., et al., 2020. Robust T cell immunity in convalescent individuals with asymptomatic or mild COVID-19. Cell. https://doi.org/10.1016/j.cell.2020.08.017
• 79:45 – Mateus, J., Grifoni, A., Tarke, A., et al., 2020. Selective and cross-reactive SARS-CoV-2 T cell epitopes in unexposed humans. Science eabd3871. https://doi.org/10.1126/science.abd3871
• 80:30 – Lv, H., Wu, N.C., Tsang, O.T.-Y., et al., 2020. Cross-reactive Antibody Response between SARS-CoV-2 and SARS-CoV Infections. Cell Reports 31, 107725. https://doi.org/10.1016/j.celrep.2020.107725

The podcast was recorded on August 20, 2020. If you want to reach out to us with comments, suggestions or other feedback, please send an e-mail to podcast at microbiology dot se or contact @bengtssonpalme via Twitter. The music that can be heard on the pod is composed by Johan Bengtsson-Palme and is taken from the album Cafe Phonocratique.

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Fun things on a Friday! First of all, we have updated our lab member page with some beautiful photos! Thanks Marcus for brining your camera today!

Second, our review of factors important for antibiotic resistance development in the environment has been recognised by FEMS Microbiology Reviews as one of the papers which have made the most impact across their portfolio. It has been added to a new (well, this is old news, so semi-new) collection of papers – ‘Articles with Impact’ – many of which are very well worth a read!

Have a nice weekend!

The fall is here and with it comes the arrival of three new group members. This fall, we are joined by Mahbuba Lubna, Sebastian Wettersten and Marcus Wenne. All three are master students from the University of Gothenburg and they will work on very different things.

Mahbuba will work together with Emil Burman on genes responsible for invasion in microbial communities (primarily THOR), expanding on Emil’s work and testing new and existing candidate genes in a wider diversity of conditions.

Sebastian will work on improving Metaxa2, making its classifications better and also enabling even better automation of database creation. Hopefully this will increase the pace of the Metaxa2 development, which has been stagnating a bit over the last two years.

Marcus, finally, will work together with Anna Abramova on analysing antibiotic resistance in a huge metagenomic dataset previously generated in the lab.

This means that we are now seven people in the lab (so if it weren’t for the covid-associated work from home recommendations, it would start to get crowded…) We welcome our three new members and look forward to an exciting fall!