Biochemistry Off the Shelf Jerry L. Wilson California State University, Sacramento, CA 95819 Many of the traditional biochemistry experiments. especially those invol\.ing metahdic reactions, use animal tissues and fluids as a source of the enzymes needed for the experiment. .4 compelling argument against the use of animal sources for under~raduatebiochemical experiments is that it often constitutei an unnecessary use of animals in scientific experimentation. As scientists, we should make everv effort to use animals only in experimentation when the information or learning experience can be obtained in no other wav. In spite of thefact that one's class may be mostly premed, relevance is not necessarily increased by using animal tissue. Chemists, of all people, should he aware that the properties of proteins are not functions of their sources. Students should he made aware that, removed from the cell, plant proteins are indistinguishable from animal proteins in their general properties. Rather than using fresh animal tissue for enzymes or metabolic experiments, I suggest using non-animal sources that are relatively inexpensive, readily available, and require no special storage or handling facilities beyond a refrigerator. Enzymes and Other Protelns Plant material is an excellent source of some enzvmes and can even he used us a source of solutions of proteins. Seeds, which can be bought in hulk and wnvenientlv stored. are a good source of phosphatases and other hydrol&ic enzymes. I have used bean seeds as old as five vears which still vielded active acid phosphatase. Seeds can beground ro a useful s i ~ e fur extractim of prutein in a Wilev mill or a Warinr- hltnder, or even a coffee bean grinder. The local supermarket is a convenient source of sufficiently fresh plant material. Spinach, bean sprouts, cauliflower, and potatoes have all been used as sources of enzymes that are often thought of as animal enzymes, e.g., phosphorylase (I). Bean sprouts (Phaseolus aureus) can be grown easily if not available from the supermarket. After soaking seeds overnight in water, the seeds are spread on top of a 2-3-in. layer of dampened vermiculite in a shallow plastic pan. The seeds are covered with 1 in. of vermiculite and thoroughly wet. The pan is placed in a dark cabinet for 3-5 days. Depending on the temperature of the cabinet, this will produce etiolated seedlings 2-5 in. high. These shoots can be used whole or cut up into roots, stems, and cotyledons. The stems are a good source of mitochondria (14). The seeds can be obtained from health foodstores and stores that specialize in oriental foods. Oneshould not forget the common hen eee. For our undergraduate lab we havefound that solutions-gf egg white protein are excellent for testine.. the eeneral nronerties of soluble . . protein, such as precipitation u,ith variouschuotropic agents and studvinr the effects of temDerature and DH on rotei in solubilit;. F& large egg ~ h i t e s - ~liter e r of b;ffer a t p~ 7.0, stirred for 30 min and filtered through a glass wool plug, yield a solution containing about 10 mg proteinlml and which is stable for about one week if kept refrigerated. If fresh eggs (
