The degradation of C.I. Direct red 80, a polyazo dye, was investigated using Bacillus firmus immobilized by entrapment in tubular polymeric gel. This bacterial strain was able to completely decolorize 50 mg/L of C.I. Direct red 80 under anoxic conditions within 12 h and also degrade the reaction intermediates (aromatic amines) during the subsequent 12 h under aerobic conditions. The tubular gel...

The MM281 strain of Salmonella typhimurium which possesses mutations in each its three known Mg2+ transport systems and requires 100 mM Mg2+ for growth was used to screen a genomic library from the gram-positive alkaliphilic bacterium Bacillus firmus OF4 for clones that could restore the ability to grow without Mg2+ supplementation. Of the clones obtained, five also conferred sensitivity to Co2...

Compared with morphological and life history traits, quantitative genetic variation of metabolic and related traits in animals has been poorly studied. We used flow-through VCO(2) respirometry and simultaneous activity measurement on nymphs of the sand cricket (Gryllus firmus) from inbred lines to estimate broad-sense heritability of four metabolic variables. In addition, we measured a number o...

Characterizing the extent of genomic differentiation between recently diverged lineages provides an important context for understanding the early stages of speciation. When such lineages form discrete hybrid zones, patterns of differential introgression allow direct estimates of which genome regions are likely involved in speciation and local adaptation. Here we use a backcross experimental des...

Although the differential flow of metabolites through alternate pathways of intermediary metabolism is thought to be an important functional cause of life-history trade-offs, this phenomenon remains understudied. Using a radiolabeled amino acid, we quantified genetic differences in in vivo amino acid metabolism between morphs of the wing-polymorphic cricket Gryllus firmus that trade off early-a...

Virtually no published information exists on insect endocrine traits in natural populations, which limits our understanding of endocrine microevolution. We characterized the hemolymph titers of juvenile hormone (JH) and ecdysteroids (ECDs), two key insect hormones, in field-collected short-winged, flightless (SW) and long-winged, flight-capable (LW(f)) morphs of the cricket Gryllus firmus. The ...

Wing polymorphism is a powerful model for examining many aspects of adaptation. The wing dimorphic cricket species, Gryllus firmus, consists of a long-winged morph with functional flight muscles that is capable of flight, and two flightless morphs. One (obligately) flightless morph emerges as an adult with vestigial wings and vestigial flight muscles. The other (plastic) flightless morph emerge...