Linked Life Data

7764986

Source:http://linkedlifedata.com/resource/pubmed/id/7764986

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-8-4
pubmed:abstractText
Certain higher plants synthesize and accumulate glycine betaine, a compound with osmoprotectant properties. Biosynthesis of glycine betaine proceeds via the pathway choline-->betaine aldehyde-->glycine betaine. Plants such as tobacco (Nicotiana tabacum L.) which do not accumulate glycine betaine lack the enzymes catalyzing both reactions. As a step towards engineering glycine betaine accumulation into a non-accumulator, spinach and sugar beet complementary-DNA sequences encoding the second enzyme of glycine-betaine synthesis (betaine aldehyde dehydrogenase, BADH, EC 1.2.1.8) were expressed in tobacco. Despite the absence of a typical transit peptide, BADH was targeted to the chloroplast in leaves of transgenic plants. Levels of extractable BADH were comparable to those in spinach and sugar beet, and the molecular weight, isoenzyme profile and Km for betaine aldehyde of the BADH enzymes from transgenic plants were the same as for native spinach or sugar beet BADH. Transgenic plants converted supplied betaine aldehyde to glycine betaine at high rates, demonstrating that they were able to transport betaine aldehyde across both the plasma membrane and the chloroplast envelope. The glycine betaine produced in this way was not further metabolized and reached concentrations similar to those in plants which accumulate glycine betaine naturally. Betaine aldehyde was toxic to non-transformed tobacco tissues whereas transgenic tissues were resistant due to detoxification of betaine aldehyde to glycine betaine. Betaine aldehyded ehydrogenase is therefore of interest as a potential selectable marker, as well as in the metabolic engineering of osmoprotectant biosynthesis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
B
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0032-0935
pubmed:author
pubmed:issnType
Print
pubmed:volume
193
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
155-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Metabolic engineering of glycine betaine synthesis: plant betaine aldehyde dehydrogenases lacking typical transit peptides are targeted to tobacco chloroplasts where they confer betaine aldehyde resistance.
pubmed:affiliation
Institut de Recherche en Biologie Végétale, Université de Montréal, Québec, Canada.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't