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001-es BibID:	BIBFORM046861
Első szerző:	Deák Eleonóra
Cím:	Membrane-bound and extracellular beta-lactamase production with developmental regulation in Streptomyces griseus NRRL B-2682 / Deak, E., Szabo, I., Kalmaczhelyi, A., Gal, Z., Barabas, G., Penyige, A.
Dátum:	1998
ISSN:	1350-0872 1465-2080
Megjegyzések:	A new type of beta-lactamase has been isolated and characterized in Streptomyces griseus NRRL B-2682. The enzyme has membrane-bound and extracellular forms. Biochemical characterization of some of the properties of the enzyme showed that it belongs to the class A group of penicillinases. Comparison of the membrane-bound and extracellular forms of the beta-lactamases suggests that they seem to be differently processed forms of the same enzyme. The N-terminal amino acid sequence of the extracellular form of the beta-lactamase showed a high degree of similarity to a D-aminopeptidase of another Streptomyces griseus strain. Secretion of the beta-lactamase was affected by the differentiation state of the strain since in spontaneous non-sporulating mutants only the membrane-bound form was present. In accordance with this when sporulation of the wild-type strain was inhibited it failed to secrete extracellular beta-lactamase. Addition of globomycin to the non-sporulating cells liberated the enzyme from the membrane, indicating that the protein is processed normally by signal peptidase II and a glyceride-thioether group, together with a fatty acid amide-linkage, is responsible for the attachment of the enzyme to the cellular membrane. Under sporulation-repressed conditions addition of peptidoglycan fragments and analogues or inhibition of cell wall biosynthesis by penicillin-G induced beta-lactamase secretion and also restored sporulation both in solid and submerged cultures. These results confirm that beta-lactamase secretion is tightly coupled to the sporulation process in S. griseus.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Microbiology (Reading, England). - 144 : 8 (1998), p. 2169-2177. -
További szerzők:	Szabó István (1950-) (sejtbiológus, molekuláris genetikus) Kálmánczhelyi Attila Gál Zsuzsanna (1959-) (vegyész) Barabás György (1933-) (sejtbiológus, molekuláris genetikus) Penyige András (1954-) (molekuláris genetikus)
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001-es BibID:	BIBFORM047235
035-os BibID:	(PMID)8800814
Első szerző:	Penyige András (molekuláris genetikus)
Cím:	Evidence of a role for NAD+-glycohydrolase and ADP-ribosyltransferase in growth and differentiation of Streptomyces griseus NRRL B-2682 : inhibition by m-aminophenylboronic acid / András Penyige, Eleonóra Deák, Attila Kálmánczhelyi, György Barabás
Dátum:	1996
ISSN:	1350-0872 1465-2080
Megjegyzések:	m-Aminophenylboronic acid (APBA) inhibited the germination, growth and sporulation of Streptomyces griseus NRRL B-2682 in an age- and concentration-dependent manner in submerged and solid cultures. When added to cells or cell extracts it irreversibly inhibited NAD+-glycohydrolase and ADP-ribosyltransferase activity. ADP-ribosyltransferase was more sensitive, but inhibition was not complete, even in the presence of 10 mM APBA. The in vivo effects of the inhibitor correlated with its in vitro effect on ADP-ribosylation and on the profile of ADP-ribosylated endogenous proteins. The physiological importance of ADP-ribosyltransferase was supported by the observation that APBA strongly inhibited the growth of a non-sporulating and NAD+- glycohydrolase-negative mutant of the parental strain. The resistance of S. griseus NRRL B-2682 strains able to grow in the presence of APBA was due to permeability factors. A comparison of the ADP-ribosylated protein profiles of S. griseus NRRL B-2682 grown under various conditions showed similarities, but also specific differences. The results suggest that the ADP-ribosyltransferase of S. griseus NRRL B-2682 is an indispensable enzyme for growth and differentiation of the strain. It may regulate the activity of key enzymes or developmental proteins by responding to intra- and extracellular conditions.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Microbiology (Reading, England). - 142 : 8 (1996), p. 1937-1944. -
További szerzők:	Deák Eleonóra Kálmánczhelyi Attila Barabás György (1933-) (sejtbiológus, molekuláris genetikus)
Internet cím:	Szerző által megadott URL DOI Intézményi repozitóriumban (DEA) tárolt változat
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001-es BibID:	BIBFORM046862
Első szerző:	Penyige András (molekuláris genetikus)
Cím:	Modification of Glutamine Synthetase in Streptomyces griseus by ADP-Ribosylation and Adenylylation / Penyige, A., Kalmanczhelyi, A., Sipos, A., Ensign, J. C., Barabas, G.
Dátum:	1994
ISSN:	0006-291X
Megjegyzések:	Addition of NH+4 to Streptomyces griseus 2682 cells grown in NO?3 containing medium resulted in a rapid decline in glutamine synthetase activity due to covalent modification of the enzyme. The NH+4 promoted inactivation of the enzyme was inhibited by the ADP-ribosyltransferase inhibitor 3-methoxybenzamide. In the presence of ADP-ribosyltransferase activity the purified glutamine synthetase was also inhibited by NAD+ in a concentration-dependent manner. ADP-ribosylation of glutamine synthetase was demonstrated in vitro by showing the incorporation of labeled ADP-ribose from [?-32P]NAD+ into glutamine synthetase subunits. Beside ADP-ribosylation, adenylylation of glutamine synthetase was also shown in S. griseus since phosphodiesterase I treatment reactivated the enzyme in crude extracts of NH+4-shocked cells. Glutamine synthetase was also inhibited and modified by ATP in crude cellular extracts. These results suggest that in S. griseus 2682 ADP-ribosylation of glutamine synthetase could be an alternative modification to adenylylation to regulate glutamine synthetase activity.
Tárgyszavak:	Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:	Biochemical And Biophysical Research Communications. - 204 : 2 (1994), p. 598-605. -
További szerzők:	Kálmánczhelyi Attila Sipos Anikó Ensign, J. C. Barabás György (1933-) (sejtbiológus, molekuláris genetikus)
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