The α-amylase of the beetle Callosobruchus chinensis. Purification and action pattern

Callosobruchus chinensis larval amylase was isolated and purified in five steps, which included co-precipitation with glycogen and column chromatography on ECTEOLA-cellulose. The enzyme was homogeneous by disc gel electrophoresis on polyacrylamide. The alpha-amylase nature was evidenced by the action on amylopectin beta-amylase limit-dextrin, by the effect on the substrate-iodine complex and by the action pattern on several polysaccharide substrates. These action patterns are compared with those of other alpha-amylases.     

The policy chicken and the science egg. Has applied ecology failed the transgenic crops debate?

Ecology has a long history of research relevant to and impacting on real-world issues. Nonetheless problems of communication remain between policy-makers and scientists because they tend to work at different levels of generality (policy deals with broad issues, science prefers specific questions), and complexity (policy-makers want simple answers, ecologists tend to offer multi-factorial solutions) and to different timescales (policy-makers want answers tomorrow, ecologists always seem to want more time). These differences are not unique to the debate about the cultivation of transgenic crops. Research on gene flow is used to illustrate how science and policy are intimately bound together in a value-laden, iterative and messy process unlike that characterised by the ‘encounter problem—do science—make policy’ model. It also demonstrates how the gap between science and policy is often characterised by value-laden language. Scientists involved in ERA for transgenic crops may find their engagement with policy- and decision-makers clouded by misunderstanding about what one should expect from the other. Not the least of these, that science can define harm, is explored in a discussion of the UK Farm Scale Evaluations of herbicide-tolerant GM crops. The varied responses to these extensive trials highlight the problems of linking specific scientific experiments with broad policy objectives. The problems of applied ecology in the transgenic crops debate are not unique but may differ from other areas of environmental policy in the intense politicisation of the debate, the emphasis on assessment of risk and the particularly broad policy objectives.