Cell-bound alkaline phosphatase of Bacillus cereus was produced during vegetative growth and sporulation in a complex medium. Addition of glucose repressed the sporulation process and the amount of enzyme synthesized increased. The time course of alkaline phosphatase production is very similar in both sporulating and non-sporulating cells. Irrespective of sporulation, alkaline phosphatase level shows a peak of activity in the exponential phase, and another in the stationary phase of growth. This preliminary data indicates differences between B. cereus, and B. subtilis in alkaline phosphatase characteristics.

• MeSH
• alkalická fosfatasa biosyntéza   MeSH
• Bacillus cereus enzymologie   růst a vývoj   fyziologie   MeSH
• bakteriální proteiny biosyntéza   MeSH
• glukosa MeSH
• kultivační média chemie   MeSH
• spory růst a vývoj   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• alkalická fosfatasa MeSH
• bakteriální proteiny MeSH
• glukosa MeSH
• kultivační média MeSH

A two-dimensional electrophoretic method was used to show that protein degradation occurs immediately after the end of exponential growth but that its occurrence is masked in the usual assay methods for a 2-h period and that degradation is apparently nonselective with respect to protein molar mass or charge. The results suggest that considerable reutilization of internal amino acids may occur during sporulation regardless of the size of the external chase. Finally, the levels of intracellular proteinase activities present even at the end of exponential phase growth, as measured in vitro, are sufficient to account for the maximum rates of protein degradation observed in vivo.

• MeSH
• Bacillus subtilis enzymologie   metabolismus   fyziologie   MeSH
• bakteriální proteiny analýza   biosyntéza   metabolismus   MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• endopeptidasy metabolismus   MeSH
• isoelektrická fokusace MeSH
• koncentrace vodíkových iontů MeSH
• leucin analýza   metabolismus   MeSH
• matematika MeSH
• molekulová hmotnost MeSH
• spory bakteriální MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, U.S. Gov't, P.H.S. MeSH
• Názvy látek
• bakteriální proteiny MeSH
• endopeptidasy MeSH
• leucin MeSH

The rate of protein turnover in asporogenic Bacillus megaterium decreases continuously during incubation in a sporulation medium. The capability of equilibration of external amino acids with amino acids in the metabolic pool of non-growing cells was retained for at least 5 h. Leucine, while repressing the synthesis of the exocellular protease, does not significantly influence the course of protein degradation in vivo. Transfer of non-growing cells after 4 h to a fresh sporulation medium does not influence the rate of protein degradation. The gradual decrease of the rate of protein turnover in non-growing cells of the asporogenic variant is thus not an artifact caused by a decreased uptake of amino acids by cells or by conditions under which the protein turnover is determined.

• MeSH
• aminokyseliny metabolismus   MeSH
• Bacillus megaterium růst a vývoj   metabolismus   MeSH
• bakteriální proteiny metabolismus   MeSH
• kinetika MeSH
• kultivační média MeSH
• leucin metabolismus   MeSH
• spory bakteriální MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• aminokyseliny MeSH
• bakteriální proteiny MeSH
• kultivační média MeSH
• leucin MeSH

Intracellular proteolytic activity increased during incubation of the sporogenic strain of Bacillus megaterium KM in a sporulation medium together with excretion of an extracellular metalloprotease. The exocellular protease activity in a constant volume of the medium reached a 100-fold value with respect to the intracellular activity. Maximal values of the activity of both the extracellular and intracellular enzyme were reached after 3-5 h of incubation. After 7 h 20-50% cells formed refractile spores. The intracellular proteolytic system hydrolyzed denatured proteins in vitro at a rate up to 150 mug mg-1 h-1 and native proteins at a rate up to 70 mug mg-1 h-1. Degradation of proteins in vivo proceeded from the beginning of transfer to the sporulation medium at a constant rate of 40 mug mg-1 h-1 and the inactivation of beta-galactosidase at a rate of 70 mug mg-1 h-1. The intracellular proteolytic activity was inhibited to 65-88% by EDTA, to 23-76% by PMSF. Proteolysis of denatured proteins was inhibited both by EDTA and PMSF more pronouncedly than proteolysis of native proteins; 50-65% of the activity were localized in protoplasts. Another strain of Bacillus megaterium (J) characterized by a high (up to 90%) and synchronous sporulation activity was found to behave in a similar way, but the rate of protein turnover in this strain was almost twice as high. The asporogenic strain of Bacillus megaterium KM synthesized the exocellular protease in the sporulation medium, but its protein turnover was found to decrease substantially after 3-4 h. The intracellular proteolytic system of the sporogenic strain J and the asporogenic strain KM were also inhibited by EDTA and PMSF.

• MeSH
• Bacillus megaterium enzymologie   růst a vývoj   MeSH
• bakteriální proteiny metabolismus   MeSH
• EDTA farmakologie   MeSH
• endopeptidasy metabolismus   MeSH
• fenylmethylsulfonylfluorid farmakologie   MeSH
• mutace MeSH
• protoplasty enzymologie   MeSH
• spory bakteriální enzymologie   růst a vývoj   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• EDTA MeSH
• endopeptidasy MeSH
• fenylmethylsulfonylfluorid MeSH

• MeSH
• autoradiografie MeSH
• Bacillus megaterium růst a vývoj   metabolismus   MeSH
• Bacillus subtilis enzymologie   MeSH
• bakteriální proteiny biosyntéza   metabolismus   MeSH
• bakteriologické techniky MeSH
• chlorid amonný metabolismus   MeSH
• dusík metabolismus   MeSH
• elektronová mikroskopie MeSH
• izotopy uhlíku MeSH
• kultivační média MeSH
• leucin metabolismus   MeSH
• proteasy biosyntéza   MeSH
• spory bakteriální růst a vývoj   MeSH
• tritium MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• chlorid amonný MeSH
• dusík MeSH
• izotopy uhlíku MeSH
• kultivační média MeSH
• leucin MeSH
• proteasy MeSH
• tritium MeSH