Diversity: Cultural and biological

Early human populations utilized a wide range of biological resources in a tremendous diversity of environments. As a result, they possessed high levels of cultural diversity dependent on and supportive of high levels of biological diversity. This pattern changed drastically with technological innovations enabling certain human groups to break down territorial barriers and to usurp resources of other groups. The dominant groups have gone on to exhaust a whole range of resources, depleting both biological and cultural diversity. Traditions of resource conservation can, however, re-emerge when the dominant cultures spread over the entire area and the innovations diffuse to other human groups. This could change once again as genetically engineered organisms become an economically viable proposition with the accruing advantages concentrated in the hands of a few human groups: a further drastic reduction in biological and cultural diversity may ensue.

Cloning by genomic PCR and production of peanut agglutinin in Escherichia coli

Using the polymerase chain reaction, the coding sequence for peanut agglutinin (PNA) was cloned and expressed in Escherichia coli. Amplified PNA is identical to previously reported cDNA, suggesting the absence of any introns in PNA gene. Recombinant (re-) PNA forms inclusion bodies in E. coli. Production of PNA was confirmed by probing Western blots with polyclonal anti-PNA immunoglobulin G. Inclusion bodies were solubilized with 6 M guanidine-HCl and renatured by rapid dilution in the presence of metal ions. The renatured lectin was then purified by affinity chromatography. The re-lectin shows carbohydrate-binding properties similar to the natural PNA. This expression system provides a model for future mutagenesis studies of the carbohydrate-binding site and thus facilitates ongoing efforts to explore the molecular basis for the specificity of lectin-carbohydrate interaction.