FLORES GARCÍA , Enrique

Nitrate is widely used as a nitrogen source by cyanobacteria, in which the nitrate assimilation structural genes frequently constitute the so-called nirA operon. This operon contains the genes encoding nitrite reductase (nirA), a nitrate/nitrite transporter (frequently an ABC-type transporter; nrtABCD), and nitrate reductase (narB). In the...

Se han estudiado las primeras fases de la utilización del nitrato en la cianobacteria anacystis nidulans. En la entrada del nitrato a la célula participa una permeasa que lo transporta activamente. El nitrato se reduce hasta el termino de amonio utilizando directamente electrones generados en la fotolisis del agua. Finalmente el amonio se...

A region of the genome of the filamentous, nitrogen-fixing, heterocyst- forming cyanobacterium Anabaena sp. strain PCC 7120 that contains a cluster of genes involved in nitrate assimilation has been identified. The genes nir, encoding nitrite reductase, and nrtABC, encoding elements of a nitrate permease, have been cloned. Insertion of a gene...

Expression of the nitrate assimilation nir operon in the filamentous, heterocyst-forming cyanobacterium Anabaena sp. strain PCC 7120 requires the action of both the global nitrogen control transcription factor NtcA and the pathway-specific transcriptional regulator NtcB. In the genome of this cyanobacterium, the ntcB gene is found in a cluster...

The effect of the nitrogen source on the cellular activity of ferredoxin-nitrate reductase in different cyanobacteria was examined. In the unicellular species Anacystis nidulans, nitrate reductase was repressed in the presence ofammonium but de novo enzyme synthesis took place in media containing either nitrate or no nitrogen source, indicating...

Cyanobacteria are generally capable of photoautotrophic growth and are widely distributed on Earth. The model filamentous, heterocyst‐forming strain Anabaena sp. PCC 7120 has long been considered as a strict photoautotroph but is now known to be able to assimilate fructose. We have previously described two components of ABC glucoside uptake...