Bromine – an element with atomic number 35 and the chemical symbol Br – is the 28th chemical element essential for tissue development in humans and all other animals, says a team of researchers led by Prof Billy Hudson of Vanderbilt University School of Medicine.

Twenty seven, among the 92 naturally-occurring chemical elements, were considered to be essential for human life – until now.

There is a 28th – bromine, according to Prof Hudson and his colleagues.

In a study, published in the journal Cell, they showed that Drosophila fruit flies died when bromine was removed from their diet but survived when bromine was restored.

“Without bromine, there are no animals. That’s the discovery,” Prof Hudson said.

The foundation for this discovery goes back 30 years.

In the mid-1980s, curiosity about two rare kidney diseases led Prof Hudson to the discovery of two previously unknown proteins that twist around each other to form the triple-helical collagen IV molecule, like cables supporting a bridge. Disease results when these cables are defective or damaged.

In 2009, another research team discovered a novel sulfilimine bond between a sulfur atom and a nitrogen atom that acts like a ‘fastener’ to connect the collagen IV molecules forming scaffolds for cells.

A defective bond may trigger the rare auto-immune disease Goodpasture’s syndrome. That discovery led to simple question: how is the bond formed?

In 2012, co-authors of the current discovery – Vanderbilt University scientists Prof Gautam Bhave and Dr Christopher Cummings – led the study that found the answer – the enzyme peroxidasin.

Conserved across the animal kingdom, peroxidasin also may play a role in disease. An overactive enzyme may lead to excessive deposition of collagen IV and thickening of the basement membrane, which can impair kidney function.

In the current study, Prof Hudson’s team demonstrated the unique and essential role for ionic bromide as a co-factor, enabling peroxidasin to form the sulfilimine bond.

“The chemical element bromine is thus essential for animal development and tissue architecture,” the scientists said.

The discovery has important implications for human disease.

“Multiple patient groups have been shown to be bromine deficient,” said study first author Scott McCall of Vanderbilt University School of Medicine.

“Bromine supplementation may improve the health of patients on dialysis or total parenteral nutrition, for example.”

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A. Scott McCall et al. 2014. Bromine Is an Essential Trace Element for Assembly of Collagen IV Scaffolds in Tissue Development and Architecture. Cell, vol. 157, no. 6, pp. 1380–1392; doi: 10.1016/j.cell.2014.05.009