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The main aim of the present work is the content analysis of the Portuguese National Curriculum and the Primary School textbooks where microorganisms are concerned. The content analysis through categories created a priori were used as methodology. In all analysed documents the topic microorganisms did not emerge in a clear way. However, several indirect themes related to microorganisms were found in the National Curriculum and textbooks of the Environment Study issue. These themes can be explored with pupils through experimental activities. The Science Education in primary schools can be introduced with proposals of activities involving microorganisms and contributing to a better understanding of the children's world.

The aim of this study was the bioprospection of microorganisms isolated from the effluent of the cassava flour for lipase production. Samples of bacteria, yeasts and filamentous fungi were isolated from this effluent. The experiments were carried out in Erlenmeyers flasks in the presence of "manipueira", olive oil and ammonium sulphate, at 150 rpm and 28 °C, during 8 days. The lipase production increased with the cultivation time for 45 % of the microorganisms investigated. Some microbial samples showed different peaks of lipolytic activity. The maximum lipase production reached 10.1 IU/L at pH 5.6 and the maximum productivity was 3.95 IU/L.d at pH 3.9. More research needs to be stimulated on bioprospection of microorganisms for enzyme production with the reuse of industrial wastes, avoiding environmental impact and reducing costs for biotechnological processes.

Panspermia, an ancient idea, posits that microbial life is ubiquitous in the Universe. After several decades of almost irrational rejection, panspermia is at last coming to be regarded as a serious contender for the beginnings of life on our planet. Astronomical data is shown to be consistent with the widespread distribution of complex organic molecules and dust particles that may have a biological provenance. A minuscule (10⁻²¹) survival rate of freeze-dried bacteria in space is all that is needed to ensure the continual recycling of cosmic microbial life in the galaxy. Evidence that terrestrial life may have come from elsewhere in the solar system has accumulated over the past decade. Mars is seen by some as a possible source of terrestrial life, but some hundreds of billions of comets that enveloped the entire solar system, are a far more likely primordial reservoir of life. Comets would then have seeded Earth, Mars, and indeed all other habitable planetary bodies in the inner regions of the solar system. The implications of this point of view, which was developed in conjunction with the late Sir Fred Hoyle since the 1970's, are now becoming amenable to direct empirical test by studies of pristine organic material in the stratosphere. The ancient theory of panspermia may be on the verge of vindication, in which case the entire universe would be a grand crucible of cryomicrobiology.

There exists a close correspondence between the measured infrared properties of diatoms and the infrared spectrum of interstellar dust as observed in the Trapezium nebula and toward the galactic center source GC-IRS 7. Diatoms and bacteria also exhibit an absorbance peak near 2200 Å, which is found to agree with the observed ultraviolet absorbance properties of interstellar grains. We review the observational data and consider the known properties of diatoms and bacteria. It is suggested that these characteristics are consistent with the concept of a cosmic microbiological system in which these or similar microorganisms might exist on comets, Europa and in interstellar space.