Biomaterial Database

Altered penicillin-binding components in penicillin-resistant mutants of Bacillus subtilis. 1976

C E Buchanan, and J L Strominger

Penicillin- (cloxacillin-) resistant mutants of Bacillus subtilis were isolated in a stepwise fashion and the five penicillin-binding components (PBCs) in each were examined to determine which of the proteins, if any, corresponds to the penicillin killing site. PBCs II and V were previously eliminated as the likely penicillin targett. In the present work, PBC IV showed no change in sensitivity to cloxacillin in any of the resistant mutants isolated. PBC I did not change until the fifth-step mutant, in which it could not be detected by penicillin binding. Since PBC I did not bind penicillins that are lethal for this mutant, it also cannot be the lethal target. PBC II showed increased resistance to cloxacillin in three discrete steps, i.e., in mutants 1, 4, and 5, accompanied by changes in its electrophoretic mobility. However, the sensitivity of PBC II to penicillin G changed very little. Correspondingly, the cloxacillin-resistant mutants were unaltered in their sensitivity to penicillin G in vivo. Thus, of the five PBCs found in B. subtilis, PBC II is the most likely target for killing by penicillins.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D010400	Penicillin G	A penicillin derivative commonly used in the form of its sodium or potassium salts in the treatment of a variety of infections. It is effective against most gram-positive bacteria and against gram-negative cocci. It has also been used as an experimental convulsant because of its actions on GAMMA-AMINOBUTYRIC ACID mediated synaptic transmission.	Benzylpenicillin,Benpen,Benzylpenicillin Potassium,Coliriocilina,Crystapen,Or-pen,Parcillin,Pekamin,Pengesod,Penibiot,Penicilina G Llorente,Penicillin G Jenapharm,Penicillin G Potassium,Penicillin G Sodium,Penicillin Grünenthal,Penilevel,Peniroger,Pfizerpen,Sodiopen,Sodipen,Sodium Benzylpenicillin,Sodium Penicillin,Unicilina,Ursopen,Van-Pen-G
D010403	Penicillin Resistance	Nonsusceptibility of an organism to the action of penicillins.	Penicillin Resistances,Resistance, Penicillin,Resistances, Penicillin
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D003023	Cloxacillin	A semi-synthetic antibiotic that is a chlorinated derivative of OXACILLIN.	Chloroxacillin,Sodium Cloxacillin,Cloxacillin Sodium,Syntarpen,Tegopen,Cloxacillin, Sodium,Sodium, Cloxacillin
D001412	Bacillus subtilis	A species of gram-positive bacteria that is a common soil and water saprophyte.	Natto Bacteria,Bacillus subtilis (natto),Bacillus subtilis subsp. natto,Bacillus subtilis var. natto
D001426	Bacterial Proteins	Proteins found in any species of bacterium.	Bacterial Gene Products,Bacterial Gene Proteins,Gene Products, Bacterial,Bacterial Gene Product,Bacterial Gene Protein,Bacterial Protein,Gene Product, Bacterial,Gene Protein, Bacterial,Gene Proteins, Bacterial,Protein, Bacterial,Proteins, Bacterial
D001667	Binding, Competitive	The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.	Competitive Binding