BACTERIAL DECOMPOSITION OF WOODY CELL WALLS.

The possible decomposition of the lignified cell wall by bacteria has been investigated with 66 selected bacterial strains on cross-sections of sapwood from European beech and Scots pine. None of them could deteriorate the woody cell wall, but some strains were able to decompose the non-lignified parts, like pit membranes. Of partly lignified plant organs only the non-lignified tissues were degraded, similarly to the cellulosic G-layer of tension wood fibres. After mild delignification with chlorite several bacterial strains were able to decompose the cell wall considerably. Whereas the carbohydrates were respired, the lignin part could be recovered completely in the nutrient medium or being absorbed by the bacteria without apparent changes at the molecular level. Refs.