Thiaminase is an enzyme that metabolizes or breaks down thiamine into two molecular parts.

The old name was "Aneurinase".

There are two types:

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Sources

Source include:

• Bracken (brake), Nardoo and other plants.
• Some fish including carp and goldfish.
• A few strains of bacteria like Bacillus thiaminolyticus, Bacillus aneurinolyticus, or Bacillus subtilis.
• An African silk worm, Anaphe venata

Effects

Its physiological meaning for the plant, fish, bacterial cell or insect is not known.

It was first described as the cause of highly mortal ataxic neuropathy in fur producing foxes eating raw entrails of river fish like carp in 1941.

It is also known as the etiology of cerebrocortical necrosis of cattle and polioencephalomalasia of sheep eating thiaminase containing plants.

It was once causing economical losses in raising fisheries, e.g. in yellowtail fed raw anchovy as a sole feed for a certain period, and also in sea bream and rainbow trout. The same problem is being studied in a natural food chain system.

The larvae of a wild silk worm Anaphe venata are being consumed in a rain forest district of Nigeria as a supplemental protein nutrition, and the heat resistant thiaminase in it is causing an acute seasonal cerebellar ataxia.

In 1860-61 - Burke and Wills were the first Europeans to cross Australia south to north; on their return they subsisted primarily on raw nardoo-fern and died of beriberi because of the extremely high thiaminase content in an otherwise thiamine-poor diet.

References