Background Vitamin B1 (thiamin) is essential to life; yet little is known of the regulation of its availability in marine environments or how it varies seasonally. Since microbes are the key synthesizers of the vitamin in marine environments, we here used metatranscriptomics to examine the seasonal dynamics of B1 acquisition strategies (including both uptake and synthesis pathways) in Baltic Sea bacterioplankton. Results Elevated B1-related gene expression was observed in summer, coinciding with increased temperatures and bacterial activity and decreased nutrient availability. Different bacterial taxa exhibited distinct B1 acquisition strategies. We identified filamentous Cyanobacteria of the order Nostocales as critical to sustaining B1 production during summer, potentially compensating for limited synthesis in heterotrophic bacteria, especially for 4-amino-5-hydroxymethylpyrimidine (HMP) synthesis. Also, Pelagibacterales accounted for major portions of the community transcription, primarily taking up and salvaging the B1 precursor HMP during summer. This study highlights the partitioning of B1 synthesis, salvage, and uptake among microbial taxa, underscoring that transcriptional activity was more dynamic over time than changes in the genomic potential. Conclusions We emphasize the influence of environmental conditions on microbial community dynamics and B1 cycling in general, and the potential implications of global change-induced increases in filamentous Cyanobacteria blooms on vitamin food web transfer in particular.

Early microbial exposures from maternal microbes, milk components, and the environment shape infant gut development and long-term disease risk. The review highlights mechanisms, preventive levers, and...

YouTube video by AJE Video Bytes

Scientists and clinicians working together on a pioneering project to learn more about the role of gut microbiome in childhood obesity

Malaria parasites use a protein called P47 to survive inside mosquito vectors and evade their immune defences. By adapting P47 to local vectors, they ensure compatability and transmission, making P47 ...

A landmark field study reveals widespread pollution of the Atlantic Ocean by nanoscale plastic debris — raising questions about the risk to marine ecosystems.

Lyme disease is a tick-borne disease prevalent across Europe and the US. Many patients however, do not recall a tick bite, leaving people wondering whether other arthropods like mosquitoes could be ve...

New methods for visualising and sequencing genetic material from a single cell are allowing scientists to explore fundamental questions about living systems.

Adding nematode collagen and chitin to soils could shape the microbiome, selecting for those microbes with the ability to fight these pathogen

This editorial piece co-authored by the Senior Editors at Microbiome aims to highlight current challenges in the field of environmental and host-associated microbiome research. We also take the opport...

Scientists debate age of ancient Canadian crust as Inuit leaders work to preserve the location.

Nature Communications - The microbiota vault initiative: safeguarding Earth’s microbial heritage for future generations