INVESTIGADORES
PETRUCCELLI Silvana
artículos
Título:
A practical work in the glycogen biosynthesis in E. coli.
Autor/es:
LODEIRO, A.; DILORENZO, O.; MOLINA, S. E.; SILVANA PETRUCCELLI; SORGENTINI, D.
Revista:
BIOCHEMICAL EDUCATION
Editorial:
Science Direct
Referencias:
Lugar: Albany, New York, USA; Año: 1994 vol. 22 p. 213 - 215
ISSN:
0307-4412
Resumen:
In some stress circumstances, bacteria synthesize reserve poly- mers including glycogen. 1'2 Indeed, recent investigations suggest that accumulation of reserves is the rule rather than the exception. This is perhaps not surprising since the great majority of prokaryotes live in environments that are far from the well- supplied, aereated and temperature-controlled laboratory cultures. 3 For example, nutrient stresses are frequently encoun- tered by E coli in its various natural environments, and concomitantly, a control system of its metabolic storages and needs has evolved at various levels, from signal transduction, 4 to gene expression 3'5 and enzyme activity. 2 When nitrogen, phos- phorus and/or sulphur sources become scarce, rates of dupli- cation as well as of nucleic acid and protein biosynthesis diminish, with a rise in the energy charge. 2 If an appropriate carbon source is present, this shift in energy charge state leads to net glycogen biosynthesis and an activation of the gluconeo- genesis pathwa