The coat of a potential poultry probiotic has been analyzed by researchers at the UK's Institute of Food Research, giving the first clues to how it may be used to exclude pathogenic bacteria.

Lactobacillus johnsonii has previously been shown to exclude Clostridium perfringens from the poultry gut. The bacteria makes a coat for itself that plays an important role in colonization, and the researchers have characterized what makes up the coat, giving a better idea of its role, and so, helping in the development of these bacteria as a way of combating C perfringens.


Using NMR spectroscopy, the researchers discovered that the coat is made up of two types of exopolysaccharides (EPS), which are long sugar-containing molecules that many bacteria use to encapsulate themselves. This capsule may help the bacteria to cope with environmental stress, or aid colonization and adhesion. Different bacterial strains have different EPS structures, and understanding this is important as they represent a key way bacteria interact with the world around them.

The strain of L jonhsonii is now being taken through farm-scale trials to assess its potential use to combat pathogenic infections of poultry such as C perfringens