Longitudinal study of infants born preterm (<33 weeks) or with a very low birth weight in the Ile de France region of France (SEV-IDF programme): cohort profile.

Purpose: The SEV-IDF programme aims to track infants born before 33 weeks of gestation, with very low birth weight (VLBW), neonatal encephalopathy or severe birth anomalies and perinatal disease. It employs an open, prospective, multicentric, population-based cohort approach. This report aims to describe the methodology employed to establish and manage the programme, details regarding follow-up procedures, baseline characteristics of the included infants, and highlights new research opportunities emerging from the "" (SEV-IDF) programme.

Transcripts of the genes sacB, amyE, sacC and csn expressed in Bacillus subtilis under the control of the 5' untranslated sacR region display different stabilities that can be modulated.

When Bacillus subtilis levanase (SacC), alpha-amylase (AmyE) and chitosanase (Csn) structural genes were expressed under the regulated control of sacR, the inducible levansucrase (SacB) leader region in a degU32(Hy) mutant, it was observed that the production yields of the various extracellular proteins were quite different. This is mainly due to differences in the stabilities of their corresponding mRNAs which lead to discrepancies between the steady-state level of mRNA of sacB and csn on the one hand and amyE and sacC on the other. In contrast to levansucrase mRNA, the decay curves of alpha-amylase and levanase mRNAs obtained by Northern blotting analysis did not match the decay curves of their functional mRNA.

Characterization of the rate-limiting step of the secretion of Bacillus subtilis alpha-amylase overproduced during the exponential phase of growth.

The Bacillus subtilis alpha-amylase gene, amyE, was expressed under the regulated control of sacR, the levansucrase leader region. The gene fusion including the complete amyE coding sequence with the signal peptide sequence was integrated into the chromosome of a degU32(Hy) strain deleted of the sacB DNA fragment. In this genetic contex, alpha-amylase is produced in the culture supernatant at a high level (2% of total protein) during the exponential phase of growth upon induction by sucrose.