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Pregnancy Timeline by SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
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Do you speak 'Terpene'?

Micro-organisms communicate with each other, as well as the rest of the world, through scent. If you're small, smells are a good way to stand out from the crowd. Now, research has found that two different types of micro-organisms, bacteria and fungi, use fragrance known as terpenes, to converse.

Know what is the most used language in the world? Well, it's probably 'Terpene'! Research by microbial ecologists from the Netherlands Institute of Ecology NIOO-KNAW reveals two very different groups of micro-organisms use fragrance to communicate, the most common type being terpenes.

In only one gram of soil billions of micro-organisms thrive, and they are the many 'speakers' of Terpene. On top of that, this 'chemical communication' probably works for a whole bunch of other life forms as well. The work appears in Scientific Reports, a new journal from the Nature family.

The research demonstrates that bacteria and fungi do in fact respond to each other. They hold conversations. Explains group leader Paolina Garbeva PhD, from NIOO-KNAW, Department of Microbial Ecology,Wageningen, The Netherlands : "Serratia, a soil bacterium, can 'smell' the fragrant terpenes produced by Fusarium, a plant pathogenic fungus. It responds by becoming motile and producing a terpene of its own."

Researchers established that bacteria and fungi hold conversations by studying which genes are switched 'on' by bacterium, which proteins bacteria began to produce, and finally, which fragrance.

Garbeva:"We actually believe 'terpenes' are the most popular chemical medium on our planet to communicate through. Such fragrances — or volatile organic compounds — are not just some waste product, they are instruments targeted specifically at long-distance communication between these minute fungi and bacteria."

But how widespread is this 'language of smells'? Pathogenic soil fungi such as Fusarium also have an aboveground effect — they make plants sick. Do they communicate with those plants?

"We have known for some time that plants and insects use terpenes to communicate with each other. But we've only just begun to realise that it's actually much wider. There is a much larger group of 'Terpene-speakers': micro-organisms."

Paolina Garbeva PhD, the Netherlands Institute of Ecology (NIOO-KNAW), Department of Microbial Ecology,Wageningen, The Netherlands

Terpenes are by no means the only volatile organic compounds that 'chat'. Researchers have found other such compounds in the soil as well. However, according to Garbeva's PhD student Ruth Schmidt, first author of the article : "Organisms may be multilingual, but 'Terpene' is the one that's used most."

Terpenes also are in pheromones —  those chemical signals given off by animals as scent. They appear as regular ingredients in the perfumes we wear. So, it's likely the language of terpenes is one we share as part of a vast system of chemical communication that exists between the most voluminous forms of life on earth, bacteria, fungi — and us.

The ability of bacteria and fungi to communicate with each other is a remarkable aspect of the microbial world. It is recognized that volatile organic compounds (VOCs) act as communication signals, however the molecular responses by bacteria to fungal VOCs remain unknown. Here we perform transcriptomics and proteomics analyses of Serratia plymuthica PRI-2C exposed to VOCs emitted by the fungal pathogen Fusarium culmorum. We find that the bacterium responds to fungal VOCs with changes in gene and protein expression related to motility, signal transduction, energy metabolism, cell envelope biogenesis, and secondary metabolite production. Metabolomic analysis of the bacterium exposed to the fungal VOCs, gene cluster comparison, and heterologous co-expression of a terpene synthase and a methyltransferase revealed the production of the unusual terpene sodorifen in response to fungal VOCs. These results strongly suggest that VOCs are not only a metabolic waste but important compounds in the long-distance communication between fungi and bacteria.

With more than 300 staff members and students, NIOO is one of the largest research institutes of the Royal Netherlands Academy of Arts and Sciences (KNAW). The institute specialises in water and land ecology. As of 2011, the institute is located in an innovative and sustainable research building in Wageningen, the Netherlands. NIOO has an impressive research history that stretches back 60 years and spans the entire country, and beyond.
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Apr 21, 2017   Fetal Timeline   Maternal Timeline   News   News Archive   

Having a good conversation: Soil fungus Fusarium (orange) and an unrelated soil bacteria.
Image Credit: 21 Lux photography/Heike Engel


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