ABSTRACT
Among th e cellulolytic m icroorganism s, mesophilic cellulolytic an ae ro b es p lay an im portant role in th e d igestion o f cellulosic biomass in th e rum en , sewage s lu d g e , so il, and o th e r anaerobic h ab ita ts co n ta in in g cellu lose. Work on th e u n d e rs ta n d in g of th e rum en cellulolytic anaerobes has been ongoing fo r a long time ( 1 , 2 ) to gain know ledge on problem s applicable to rum inant n u tr i t io n . Among th e most com mon cellulolytic ag en ts iso lated from th e rum en and s tu d ied u n d e r lab o ra to ry conditions a re b a c te ria belonging to F ibrobacter , B u ty - riv ib rio , E ubacterium , and Rum inococcus g en e ra . More recen tly a t tem pts have been made to ob ta in m utan ts o f some o f th e se anaerobes in o rd e r to im prove cellulose d eg rad a tio n in v itro (3 ) , and fo r mole cu la r cloning of cellu lase genes (4 ; see C hap . 2A ).
