Affiliation:
1. Dipartimento di Biologia Animale e Genetica Leo Pardi, Università degli Studi di Firenze, via Romana 17, 50125 Firenze, Italy
2. Dipartimento di Genetica e Microbiologia A. Buzzati-Traverso, and Centro di Eccellenza in Biologia Applicata, Università degli Studi di Pavia, via Ferrata 1, 27100 Pavia, Italy
Abstract
ABSTRACT
Calcium carbonate precipitation, a widespread phenomenon among bacteria, has been investigated due to its wide range of scientific and technological implications. Nevertheless, little is known of the molecular mechanisms by which bacteria foster calcium carbonate mineralization. In our laboratory, we are studying calcite formation by
Bacillus subtilis
, in order to identify genes involved in the biomineralization process. A previous screening of UV mutants and of more than one thousand mutants obtained from the European
B. subtilis
Functional Analysis project allowed us to isolate strains altered in the precipitation phenotype. Starting from these results, we focused our attention on a cluster of five genes (
lcfA
,
ysiA
,
ysiB
,
etfB
, and
etfA
) called the
lcfA
operon. By insertional mutagenesis, mutant strains carrying each of the five genes were produced. All of them, with the exception of the strain carrying the mutated
lcfA
operon, were unable to form calcite crystals. By placing transcription under IPTG (isopropyl-β-
d
-thiogalactopyranoside) control, the last gene,
etfA
, was identified as essential for the precipitation process. To verify cotranscription in the
lcfA
operon, reverse transcription-PCR experiments were performed and overlapping retrocotranscripts were found comprising three adjacent genes. The genes have putative functions linked to fatty acid metabolism. A link between calcium precipitation and fatty acid metabolism is suggested.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Reference59 articles.
1. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs
2. REQUIREMENTS FOR TRANSFORMATION IN
BACILLUS SUBTILIS
3. Anderson, S., V. D. Appanna, J. Huang, and T. Viswanatha. 1992. A novel role for calcite in calcium homeostasis. FEBS Lett. 308 : 94-96.
4. Bang, S. S., J. K. Galinat, and V. Ramakrishnan. 2001. Calcite precipitation induced by polyurethane-immobilized Bacillus pasteurii. Enzyme Microb. Technol. 28 : 404-409.
5. Barabesi, C., E. Tamburini, G. Mastromei, and B. Perito. 2003. Mechanisms of microbial calcium carbonate precipitation, p. 472-485. In R. J. Koestler, V. R. Koestler, A. E. Charola, and F. E. Nieto-Fernandez (ed.), Art, biology, and conservation: biodeterioration of works of art. Metropolitan Museum of Art, New York, NY.
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