Australian journal of biotechnology最新文献

The outline of a strategy for training technicians who will undertake biotechnology-oriented tasks as employees is the focus of this review. Technical and Further Education (TAFE) in Western Australia has recently restructured electives offered in certificate and diploma courses of Applied Science. The aim of restructuring was to allow a broader choice catering for specialized streams. With a few additions it would be possible to list a set of biotechnology options for technicians specializing in this area. After identifying employers in Western Australia, data on technician employment characteristics and training needs was gathered through a survey and used to formulate a future development strategy. In the past little attention has been given anywhere in Australia to the training needs of this group. The availability of such appropriately trained employees will increasingly be recognized as a vital link in the success of any biotechnology enterprise.

This paper examines issues concerned with the environmental release of genetically-engineered micro-organisms. Besides the obvious social and economic benefits from the technology, genetically-engineered micro-organisms can have considerable beneficial effects on environmental concerns, such as the degradation of pollutants and toxic chemical wastes, and less use of hazardous pesticides and chemicals. There may be uncertain negative effects arising from the technology. The hazards of the technology and possible policy approaches are discussed. It is concluded that, overall, the applications arising from this technology are likely to be benign, because its effects on the environment can largely be anticipated by an increase in scientific knowledge gained from field trials and greater experience with releases.

This article concludes the series on the use of chromatography for downstream processing. Although it has only scratched the surface when considering the number of parameters involved in process chromatography, it does give a broad overview including the choice of components through process standards. Pharmacia LKB Biotechnology has had more than 15 years experience in the design development and running of large scale chromatographic processes. During this time the company has gathered a vast amount of experience and information on the key points to successful product purification. Pharmacia LKB can advise on the choice of techniques and the development of a separation process up to full production scale.

Culture conditions affecting the formation of beta-galactosidase inclusion bodies in E. coli were examined. High temperature, early induction, high salt concentration and low aeration were all found to favour an increase of insoluble beta-galactosidase and the formation of visible inclusion bodies. The ratio of soluble to insoluble beta-galactosidase decreased during the course of cell growth. When assayed for beta-galactosidase activity, the inclusion bodies were enzymatically active with a specific activity of one third that of soluble beta-galactosidase. The activity remained associated with the inclusion bodies on washing with detergent and high ionic strength buffers. These results suggest that inclusion bodies can contain correctly folded protein.

The plasmid pND71, which encodes beta-glucosidase (cellobiase) activity, cloned from the cellulolytic Pseudomonad, PS2-2, was mobilized by conjugation into 10 Pseudomonas strains. The highest specific activity was produced by 17498 (pND71) and the properties of the enzyme produced from this transconjugant were studied. The enzyme was shown to be cell associated, to have a temperature optimum of 37 degrees C, a pH optimum of 7.0 and Km values of 1.33 and 2.94 mM for pNPG and cellobiose respectively. It was competitively inhibited by glucose, with a Ki of 30 mM. Evidence was obtained which suggested that the enzyme was produced constitutively and that synthesis was not repressed by glucose. When culture preparations were used in combination with Trichoderma reesei QM9414 and C30 enzyme preparations to saccharify cellulose, 17498 (pND71) was more effective than preparations of PS2-2 in acting synergistically with T. reesei to solubilize more carbohydrate and produce more glucose.