title: Deficiency of autolytic activity in Bacillus subtilis and Streptococcus pneumoniae is associated with a decreased permeability of the wall.
abstract: Autolytic-deficient mutants of Bacillus subtilis which grow as chains of non-separated bacilli have been isolated by a procedure involving filtration of mutagenized cultures through glass-sinter filters. The mutants obtained were some 80-90% deficient in both autolysins, N-acetylmuramoyl-L-alanine amidase and endo-beta-N-acetylglucosaminidase. Treatment of one of these mutants with 5 M-LiCl extracted only about 20% of the protein obtained from an equivalent amount of the autolysin-containing bacilli. Similarly, a reduction of 40-60% in LiCl-extractable protein was obtained with autolytic-deficient Streptococcus pneumoniae whether these organisms lacked the autolytic enzyme or were phenotypically deficient by growth in ethanolamine-containing medium. Chromatography on Sephadex G-100 of the protein extracted from B. subtilis and S. pneumoniae revealed that the major difference between autolytic-deficient and parent organisms was a decrease in proteins of high molecular weight. Smaller differences were observed in a second fraction which contained low molecular weight material and proteins such as the autolysins, whose elution from the column was retarded by interaction with the Sephadex. Further examination of the fractionated protein from B subtilis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis confirmed that the major difference between the extracts was in the amount of protein present and did not result from marked changes in the size of the extracted proteins. These observations suggest that autolysin deficiency in B. subtilis and S. pneumoniae results in a change in the porosity (permeability) of the bacterial wall.
mesh_terms: D000118:Acetylglucosaminidase / Q000378:metabolism*; D000581:Amidohydrolases / Q000378:metabolism*; D001412:Bacillus subtilis / Q000378:metabolism*; D001426:Bacterial Proteins / Q000032:analysis; D002463:Cell Membrane Permeability; D002473:Cell Wall / Q000378:metabolism; D002712:Chlorides; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D005954:Glucosephosphate Dehydrogenase / Q000378:metabolism; D006596:Hexosaminidases / Q000378:metabolism*; D008094:Lithium; D018021:Lithium Chloride; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D008565:Membrane Proteins / Q000032:analysis; D009154:Mutation; D009238:N-Acetylmuramoyl-L-alanine Amidase / Q000378:metabolism*; D013296:Streptococcus pneumoniae / Q000378:metabolism*; D000520:alpha-Glucosidases / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D002712:Chlorides; D008565:Membrane Proteins; D008094:Lithium; D005954:Glucosephosphate Dehydrogenase; D006596:Hexosaminidases; D000520:alpha-Glucosidases; D000118:Acetylglucosaminidase; D017038:Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase; D000581:Amidohydrolases; D009238:N-Acetylmuramoyl-L-alanine Amidase; D018021:Lithium Chloride