Subcellular distribution of enzymes involved in alpha-glucan utilization in Klebsiella pneumoniae. Proteins of cytopasm, periplasm, cytoplasmic and outer membrane.

摘要: The double-isotopic labelling technique was used to identify comprehensively proteins involved in α-glucan catabolism Klebsiella pneumoniae NCTC 9633. Cells were grown with either glycerol the presence of 3H-leucine or plus maltose 14C-leucine. Each labelled culture then fractionated into main subcellular components, i.e. cytoplasm, periplasm, cytoplasmic and outer membrane. Corresponding fractions derived from 3H-labelled 14C-labelled cells combined, analyzed by polyacrylamide gel electrophoresis under denaturing conditions. Gel slices counted for 3H- 14C-radioactivity, a positive deviation standard 14C/3H ratio being evidence protein specifically induced medium. pattern thus obtained compared properties comprising similar pathway maltodextrin utilization Escherichia coli K-12. Ample information which has been mainly genetic analysis is available about maltodextrin-utilizing enzymes E. K-12. 1. Cytoplasm. Neither amylomaltase nor phosphorylase, well-known soluble enzymes, identifiable double-labelling technique, presumably because these constitute only very minor portion all cytoplasm. 2. Periplasm. A prominent mass 43000 daltons (43 kD) found maltose-binding K-12 (44 kD). 3. Cytoplasmic At least 2 between 40 50 kD detected, seen at ≈ 15 20 kD. One may function as permease catalyzing active transport maltodextrins. 4. Outer major had 55 kD, other 18, ≈48, ≈140 have same pore (55 kD), K. could grow on 10 μM practically rate mM maltose. 140 pullulanase.