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Amine oxidase in unicellular microorganismsMethanosarcina barkeri andTetrahymena pyriformis

A comparison has been performed of catalytic properties of unicellular microorganism amine oxidases (AO) from two new enzyme sources, the bacteriumMethanosarcina barkeri and the infusoriaTetrahymena pyriformis. It was shown that the both studied AO deaminate tyramine, serotonin, and benzylamine, but do not deaminate histamine. The AO fromMethanosarcina barkeri catalyzes deamination of all three substrates at an identical rate, while the rate of tyramine deamination under effect of AO fromTetrahymena pyriformis is one order higher than the rate of serotonin deamination, and about two orders higher than the rate of benzylamine deamination. Based on the data of the substrate-inhibitor analysis, a suggestion was made about the existence of one center for the substrate binding in the AO of the studied bacterium, while several centers in the AO of the studied infusoria.     

Modeling Tetrahymena thermophila growth and protease production

Oxygen concentrations stimulated growth (maximum number of cells) and protease secretion by Tetrahymena thermophila. Agitation and aeration conditions for growth and protease secretion were optimised by a central composite design. The best optimised combination was a stirrer speed of 338 rpm and an aeration of 1 vvm. Journal of Industrial Microbiology & Biotechnology (2000) 25, 58–61. Received 24 September 1999/ Accepted in revised form 06 March 2000     

Procedure and Analysis of a Useful Method in Determining Mycelial Dry Weights from Agar Plates

The evaluation of growth by dry weight determination of fungus mycelium for agar plates was examined. The data obtained were statistically analyzed. This method was shown to be sufficiently accurate to be used as an investigative tool.     

Urbanization and Identity Dissonance: A Guajiro Case

The results of this study indicate that urbanization has the effect of significantly altering the Guajiro's sense of ideal and feared identity. It was hypothesized that an attempt would be made to minimize dissonance between the ideal and the real or "true" self which the individual privately acknowledges. However, there is found to be considerable dissonance between ideal and real identities, with the latter actually including many components of feared identity. Defective socialization in the city is suggested as a possible reason for failure to achieve ideal standards.     

Feasible mechanisms for algal digestion in the king angelfish

To determine the ability of the king angelfish Holacanthus passer to digest algae, three algal species were immersed in acidic conditions similar to that found in the stomach of fish. Only one of them was not susceptible to acidic lysis; two were affected after 40 and 60 min at pH 2·0. King angelfish have an expanded region of the intestine called here the hindgut chamber (HC) containing populations of micro-organisms. Some of these micro-organisms have the capacity to grow in cellulose, agar, and alginic acid; the main components of algal cell walls. Micro-organisms grew in carboxymethylcellulose cultures under aerobic and micro-aerobic conditions. The HC is highly vascularized, which could increase absorptive efficiency of material digested in it.     

Externally attached radio transmitters do not affect the parental care behaviour of rock bass

Turning, pectoral fin and caudal fin rates and time spent on the nest of male rock bass Ambloplites rupestris , engaged in parental care, were not affected after the attachment of external radio transmitters. Reproductive success was similar between treatment and control fish. Micro external radio transmitters can be used on small fishes for studying parental care duration and post-care movement without altering their behaviour.