NIETO GUTIÉRREZ , Joaquín José

La norma morfogenética cortical de división en H. similisy H. muscorum es similar a la descrita para otros oxytriquidos aunque difieren en el origen del cirro bucal del protero y en el numero de primordios de la ciliación dorsal. La morfogénesis de regeneración subsiguiente al tratamiento con urea en estas dos especies y en G. steinii ...

A total of 232 metal-tolerant bacterial strains were isolated from water and sediment samples collected in different hypersaline environments located in Cádiz, Huelva and Morón de la Frontera (Spain). They were isolated on a medium containing mercury, chromium, cadmium, copper or zinc. These halotolerant isolates were analyzed by numerical...

The moderately halophilic heterotrophic aerobic bacteria form a diverse group of microorganisms. The property of halophilism is widespread within the bacterial domain. Bacterial halophiles are abundant in environments such as salt lakes, saline soils, and salted food products. Most species keep their intracellular ionic concentrations at low...

The role of light as an energy source for slightly aereated cultures of halobac­ teria was studied, using continuous cultures with low nutrient concentrations and a low oxygen supply. A series of experiments were carried out with non­ illuminated and differently illuminated cultures and with ditferent oxygen transfer rates. Under low oxygen...

Sixty-eight halobacteria, including both culture coUection strains and fresh isolates from widely dift'ering geographical areas, were tested for susceptibility to arsenate, cadmium, chromium, cobalt, copper, lead, mercury, nickel, silver, and zinc ions by an agar dilution technique. The culture collection strains showed dift'erent...

The extremely halophilic archaebacterium Halococcus morrhuae CCM 537 was found to contain'' a plasmid, pHM2, of 6.0 kb. A restriction map was constructed. Southern hybridization of pHM2 DNA to DNA extracted from other Halococcus sp. strains revealed the presence of a similar plasmid in one other strain. A plasmid of Halobacterium trapanicum...

The cortical morphogenesis of regeneration in Histriculus similis has been studied in this work at level of electronic microscopy. The first signs of the regeneration process become evident one hour after the treatment with urea. During the early steps of the cortical morphogenesis of regeneration, the oral primordium , paroral ciliation...

Elucidating the mechanisms controlling the synthesis of hydroxyectoine is important to design novel genetic engineering strategies for optimizing the production of this biotechnologically relevant compatible solute. The genome of the halophilic bacterium Chromohalobacter salexigens carries two ectoine hydroxylase genes, namely ectD and ectE,...

Hydroxyectoine overproduction by the natural producer Chromohalobacter salexigens is presented in this study. Genetically engineered strains were constructed that at low salinity coexpressed, in a vector derived from a native plasmid, the ectoine (ectABC) and hydroxyectoine (ectD) genes under the control of the ectA promoter, in a...

A plasmid has been isolated for the first time from moderately halophilic eubacteria. Halomonas elongata, Halomonrrs halmphila, Deleya halophila and Vibrio costkola were found to harbour an 11.5 kbp plasmid (pMH1). The plasmid was isolated and characterized after transformation into Escherichia coh'JM101 cells. A restriction map was...

The osmoregulatory pathways of the moderately halophilic bacterium Halomonas elongata DSM 3043 have been investigated. This strain grew optimally at 1.5 to 2 M NaCl in M63 glucose-defined medium. It required at least 0.5 M NaCl for growth, which is a higher concentration than that exhibited by the H. elongata type strain ATCC 33173. Externally...

The role of choline in osmoprotection in the moderate halophile Halomonas elongata has been examined. Transport and conversion of choline to betaine began immediately after addition of choline to the growth medium. Intracellular accumulation of betaine synthesized from choline was salt dependent up to 2.5 M NaCl. Oxidation of choline was...