Meat stored at 1 to 2 C under low oxygen tensions, either in gas-impermeable packs or in controlled atmospheres, occasionally exhibited an undesirable green exudate. The green pigment was identified spectrophotometrically as sulfmyoglobin. The conversion of myoglobin to sulfmyoglobin resulted from the production of H(2)S by bacteria tentatively identified as Pseudomonas mephitica. This organism...

A hallmark feature of several pathogenic microbes is the distinctive color of their colonies when propagated in the clinical laboratory. Such pigmentation comes in a variety of hues, and has often proven useful in presumptive clinical diagnosis. Recent advances in microbial pigment biochemistry and the genetic basis of pigment production have sometimes revealed a more sinister aspect to these c...

Meat stored at 1 to 2 C under low oxygen tensions, either in gas-impermeable packs or in controlled atmospheres, occasionally exhibited an undesirable green exudate. The green pigment was identified spectrophotometrically as sulfmyoglobin. The conversion of myoglobin to sulfmyoglobin resulted from the production of H2S by bacteria tentatively identified as Pseudomonas mephitica. This organism p...

INTRODUCTION .......................................... 403 COLOR VISION .......................................... 405 RED AND GREEN PIGMENTS ................................. 406 Psychophysics of Red~Green Color Blindness ....................... 406 Molecular Genetics of RedIGreen Color Blindness .................... 407 Variation in Normal Color Vision .............................. 409 Blue...

Rod and cone photoreceptor cells that are responsible for scotopic and photopic vision, respectively, exhibit photoresponses different from each other and contain similar phototransduction proteins with distinctive molecular properties. To investigate the contribution of the different molecular properties of visual pigments to the responses of the photoreceptor cells, we have generated knock-in...

The nucleotide sequence of the red-sensitive visual pigment gene, R007Af, in the fish Astyanax fasciatus, from the initiation codon to the stop codon of this gene, including introns, is 1,592 bp, making it the shortest visual pigment gene known in vertebrates. Analysis of this and other homologous sequence data suggests that vertebrates initially had two duplicate genes and that each ancestor o...

Chlorophyll (Chl) b is a ubiquitous accessory pigment in land plants, green algae, and prochlorophytes. This pigment is synthesized from Chl a by chlorophyllide a oxygenase and plays a key role in adaptation to various environments. This study characterizes a rice mutant, pale green leaf (pgl), and isolates the gene PGL by using a map-based cloning approach. PGL, encoding chlorophyllide a oxyge...

The quantitative determination of chlorophyll (Chl) a, Chl b, and carotenoids in a wholepigment extract of green plant tissue by UVVIS spectroscopy is complicated by the choice of sample, solvent system, and spectrophotometer used. The various plant pigments absorb light in overlapping spectral regions, depending on the system selected. This unit discusses methods used to account for such overl...

Juan Moreno* and José Luis Osorno Departamento de Ecologı́a Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, J. Gutiérrez Abascal 2, E-28006 Madrid, Spain Permanent address: Departamento de Ecologı́a Evolutiva, Instituto de Ecologı́a, Universidad Nacional Autónoma de México, AP 70-275, México D.F., 04510 México *Correspondence: E-mail: [email protected] Abstract Avian egg colour has been e...