Publication Date
1993
Description
A number of rumen bacteria, fungi and protozoa are involved in fibre digestion in the rumen. Recombinant DNA technology bas allowed the isolation and characterisation of key genes coding for several enzymes involved in fibre degradation. The main species that have been examined are the bacteria Ruminococcus spp., Fibrobacter succinogenes and the anaerobic fungus Neocallimastix patriciarum. Genes coding for endo--1,4-glucanases and xylanase are common amongst all these organisms, but we will concentrate on recent advances in the genetics of plant fibre digestion by N. patriciarum, which contains genes coding for relatively high level activity exo- 1,4-glucanase which may be crucial for complete cellulose hydrolysis. In addition genes coding for non-specific plant-cell-wall-hydrolysing activities have been characterised. Such genes coding for broad spectrum plant-cell-wall-degrading enzymes may be particularly important for the early invasion of plant tissues by the rumen fungi. Regulation of the expression of genes coding for plant cell wall degradation will be discussed. Transformation of rumen bacteria appears to be very strain specific and may pose problems in future modification of rumen function.
Citation
Orpin, C G. and Xue, G, "Genetics of Fibre Degradation in the Rumen, Particularly in Relation to Anaerobic Fungi, and its Modification by Recombinant DNA Technology" (2024). IGC Proceedings (1993-2023). 9.
https://uknowledge.uky.edu/igc/1993/session34/9
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
Genetics of Fibre Degradation in the Rumen, Particularly in Relation to Anaerobic Fungi, and its Modification by Recombinant DNA Technology
A number of rumen bacteria, fungi and protozoa are involved in fibre digestion in the rumen. Recombinant DNA technology bas allowed the isolation and characterisation of key genes coding for several enzymes involved in fibre degradation. The main species that have been examined are the bacteria Ruminococcus spp., Fibrobacter succinogenes and the anaerobic fungus Neocallimastix patriciarum. Genes coding for endo--1,4-glucanases and xylanase are common amongst all these organisms, but we will concentrate on recent advances in the genetics of plant fibre digestion by N. patriciarum, which contains genes coding for relatively high level activity exo- 1,4-glucanase which may be crucial for complete cellulose hydrolysis. In addition genes coding for non-specific plant-cell-wall-hydrolysing activities have been characterised. Such genes coding for broad spectrum plant-cell-wall-degrading enzymes may be particularly important for the early invasion of plant tissues by the rumen fungi. Regulation of the expression of genes coding for plant cell wall degradation will be discussed. Transformation of rumen bacteria appears to be very strain specific and may pose problems in future modification of rumen function.
