anti-bacterialagents bacteria bacterialcellsurfaces bacterialcellwalls bacterialphysiologicalphenomena betalactamantibiotics biophysics carrierproteins cellmembrane cellmembranes chemistry congresses cytology drugeffects histocytochemistry lactams metabolism methods microbiologicaltechniques microscopy penicillins pharmacology physiologicaleffect physiology plantcellsandtissues plantcellwalls plantcytochemistry plantphysiologicalphenomena plants proteinbinding qk725p939p1974 qk725s9891984s qw52a62851987 qw52b1311973 qw52h227b1984 qw52m623551991 technique ultrastructure