📰 Marine bacteria pioneers in the degradation of fresh macroalgae


Macroalgae are the main producers of organic matter in coastal areas. Scientists were interested in the strategies implemented by a marine bacterium to attack fresh macroalgae tissue and initiate its degradation. Understanding these degradation mechanisms offers promising tools view (Sight is the sense that allows us to observe and analyze the environment through reception and …) to optimize the transformation processes of biomass (In ecology, biomass is the total amount of matter (mass) of all species …) algae. This work is published in the journal the ISME Journal.

© Maéva Brunet Figure: Growth of Z. galactanivorans from pieces of seaweed. Shown on the right are photos of pronounced degradation of algal tissues in the presence of Z. galactanivorans.

Like terrestrial plants, macroalgae are producing organisms organic material (Organic matter (OM) is the carbonaceous matter typically produced by …) through the photosynthesis (Photosynthesis (Greek φῶς phōs, light and …) and are therefore the basis of food chains. They form a continuous ribbon along the ribs which, in terms of area (Area or surface is a measure of an area. By metonymy, we often designate …) and productivity, is comparable to the forest (A forest or forest massif is a wooded expanse, relatively dense, …) Amazonian. The degradation and re-injection towards higher trophic levels of this considerable stock of it matters (Matter is the substance that makes up any body having a tangible reality. Its …) organic (Organic chemistry is a branch of chemistry that deals with the description and study of a great …) they are mainly managed by heterotrophic marine bacteria. However, and contrary to the use of purified algae compounds, the bacterial mechanisms that regulate the degradation of intact algae as they occur in nature remain unknown at the moment. day (The day or day is the interval between sunrise and sunset; it is the …).

Scientists have begun to discover the strategies employed by the bacterium (Bacteria (bacteria) are prokaryotic single-celled living organisms, characterized …) Zobellia galactanivorans for using fresh seaweed. Z.galactanivorans was cultivated in microcosms with the only source of carbon (Carbon is a chemical element of the family of crystallogens, symbol C, …) fabric pieces of three different brown algae (Laminaria digitata, Toothed fucus And Ascophyllum nodoso) collected directly fromshoreline (The shoreline is the part of the coast located between the highest and highest known levels …) from Roscoff (Roscoff is a commune in the Finistère department, in the Brittany region, in France ….). The results demonstrate the pioneering behavior of Z.galactanivorans by its ability to initiate the attack on the tissues of the three species of algae tested. Pronounced signs of degradation are also quickly visible with the algae tissue. The contact physicist (Physics (from the Greek φυσις, nature) is etymologically the …) between the target bacteria and algae it is not necessary to observe a decomposition (In biology, decomposition is the process by which organized bodies, be they …), revealing the key role of extracellular enzymes in the early stages of degradation. The new ecological niches exposed by these secreted enzymes could foster the growth of other less specialized communities acting opportunistically. Indeed, it was shown during the co-culture experiments that such a strain Tenacibaculum was able to grow only from algal tissues in the presence of Z.galactanivorans.

The study of the level of expression of the genes of Z.galactanivorans allowed to highlight poorly characterized metabolic pathways induced specifically during the use of fresh algae. In particular, it seems that some groups of genes dedicated to the use of specific algal polysaccharides play a crucial role, everything (The whole understood as the set of what exists is often interpreted as the world or …) such as the type IX secretion system and response mechanisms a fatigue (Stress (“constraint” in English), or general syndrome …) caused by the defenses of theseaweed (Algae are living beings capable of photosynthesis whose life cycle is …).

This study provides the first information on bacterial degradation strategies of fresh algal biomass. This opens the way for the development of biological pretreatment processes of this biomass for the production of molecules with high added value, which constitute alternatives (Alternatives (original title: Destiny Three Times) is a published novel by Fritz Leiber …) less wasteful in energy terms than the existing physico-chemical processes.

To know more:
Consumption of fresh macroalgae induces specific catabolic pathways, stress reactions and type IX secretion in pioneers of marine flavobacteria degraders
Maeva Brunet, Nolwen Le Duff, Tristan Barbeyron, François Thomas.
The ISME Newspaper May 19, 2022 DOI: 10.1038 / s41396-022-01251-6

Integrative Biology Laboratory of Marine Models (CNRS / Sorbonne University). Roscoff Biological Station. George Teissier Square. 29680 Roscoff.

Francois Thomas – Researcher (A researcher (female researcher) refers to a person whose job is to do research …) CNRS (The National Center for Scientific Research, better known by the acronym CNRS, is the largest …) at the Laboratory of Integrative Biology of Marine Models (CNRS / Sorbonne University) – ftthomas on

Did you like this article? Do you want to support us? Share it on social networks with your friends and / or comment on it, this will encourage us to post more similar topics!


Leave a Comment