In this paper we report results on second-harmonic generation ~SHG! from aqueous suspensions of the purple membrane of Halobacterium halobium. A detailed theory describing this SHG signal is supported by results for the angular distribution of the harmonic emission and validated by experimental measurements with circularly polarized pump radiation—a condition that normally precludes SHG. Hence ...

Sinusoidal light stimuli have been used to elicit photoresponses in Halobacterium halobium at various periods of the stimulus. Cycle histograms and histograms of the times between consecutive reversals are used to illustrate the responses, and the method used to obtain sinusoidally modulated intense light (with periods up to 1 s) is described.

The malic enzyme from Halobacterium cutirubrum requires monovalent cations for both activation and stabilization. NaCl, the best stabilizer, is ineffective as activator; NH(4)Cl, the best activator, is a poor stabilizer. These results support the idea that the roles of salts in both processes are different.

Genetic and nutritional analyses of mutants of the extremely halophilic archaeon Halobacterium sp. strain NRC-1 showed that open reading frame (ORF) Vng1581C encodes a protein with nucleoside triphosphate:adenosylcobinamide-phosphate nucleotidyltransferase enzyme activity. This activity was previously associated with the cobY gene of the methanogenic archaeon Methanobacterium thermoautotrophicu...

Halobacterium sp. NRC-1 insoluble membrane and soluble cytoplasmic proteins were isolated by ultracentrifugation of whole cell lysate. Using an ion trap mass spectrometer equipped with a C18 trap electrospray ionization emitter/micro-liquid chromatography column, a number of trypsin-generated peptide tags from 426 unique proteins were identified. This represents approximately one-fifth of the t...

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Anonymous probes from the genome of Halobacterium salinarium GRB and 12 gene probes were hybridized to the cosmid clones representing the chromosome and plasmids of Halobacterium salinarium GRB and Haloferax volcanii DS2. The order of and pairwise distances between 35 loci uniquely cross-hybridizing to both chromosomes were analyzed in a search for conservation. No conservation between the geno...

We report the complete sequence of an extreme halophile, Halobacterium sp. NRC-1, harboring a dynamic 2,571,010-bp genome containing 91 insertion sequences representing 12 families and organized into a large chromosome and 2 related minichromosomes. The Halobacterium NRC-1 genome codes for 2,630 predicted proteins, 36% of which are unrelated to any previously reported. Analysis of the genome se...

Halobacterium are salt loving microorganism, which thrives in the salt lake, and seawater where there is an elevated salt concentration. They have the capacity to balance the osmotic effect of the outside environment and resist against the dehydrating effects of the salts. Their novel characteristics and capacity for large scale culturing make Halobacterium potentially valuable for biotechnolog...