Biochemical Aspects of Lipid Storage and Utilization in Animals

The high energy content of lipids makes these compounds attractiveto active metazoans as alight form of fuel storage. Animalshave evolved complex systems of enzymes and transport proteinsin order to utilize lipids for the generation of energy. Whilethe enzymatic systems responsible for lipid synthesis and oxidationare probably similar in all metazoans, mechanisms for controlof the rates of these processes differ with taxonomic group.The means by which lipids are transported through the body fluidsof metazoans also show phylogenetic variation. Complete, quantitativedata on the mechanisms and rates of lipid digestion, synthesis,transport and utilization are available for only a very fewmammals, birds and insects. This would seem to be a very fertilefield for comparative physiologists.     

The prevalence of pathogens in honey bee (Apis mellifera) colonies infested with the parasitic mite Varroa jacobsoni

The prevalence of nine honey bee viruses in samples of dead adult bees from Apis mellifera colonies in the Netherlands and Germany infested with the parasitic mite Varroa jacobsoni was compared with virus incidence in uninfested colonies in Britain. In colonies with low mite populations the viruses present and their incidence during the year were similar to the results obtained from British colonies. However, in marked contrast with findings in Britain, acute paralysis virus (APV) was the primary cause of adult bee mortality in German honey bee colonies severely infested with V. jacobsoni. Dead brood from unsealed and sealed infested cells from German colonies with high mite populations also contained much APV. The evidence suggests that V. jacobsoni activates APV replication in adult bees by its feeding behaviour and transmits virus from adult honey bees to pupae. In addition, adult bees, in which APV is multiplying, transmit the virus to unsealed brood in the larval food.     

Intraspecies Variability in the Esterases and Acid Phosphatases of Paramecium jenningsi and Paramecium multimicronucleatum: Assignment of Unidentified Paramecia; Comparison with the P. aurelia Complex1

ABSTRACT. Enzyme electrophoresis was exploited to identify stocks of paramecia previously not identified to particular species. Stocks collected in India and one from Panama belong to Paramecium jenningsi, while others collected in Panama or in Brazil are assignable to syngen 2 of P. multimicronucleatum on the basis of similarity of their esterase and acid phosphatase phenotypes. Inclusion of these doubled the numbers of stocks available in the two species, thereby facilitating examination of intraspecies variation and comparison of particular features of intraspecies variation found for the P. aurelia complex. Variant stocks were observed in P. jenningsi and in syngens 2, 3, and 4 of P. multimicronucleatum. In some cases the variant lacked the enzyme; in others, a change in mobility of the enzyme occurred that resulted in an electrophoretic form similar to one common in another species. Unique phenotypes were displayed by the variants of syngen 2 in P. multimicronucleatum. Hypervariability for Esterase B was observed in this syngen, where, in addition, several subtypes were seen for three other esterases. Unique phenotypes and hypervariability were also noted in P. biaurelia. Clustered variations were observed in these species and in the P. aurelia species. Unlike the situation for members of the aurelia complex, where lack of geographical differentiation between stocks in the same species is a unique feature, some such differentiation does occur in P. multimicronucleatum-2. The frequency of variant stocks in P. jenningsi was similar to that observed in the aurelia sibling species. In contrast, a significantly higher frequency of variant stocks was found in syngens 2, 3, and 4 of P. multimicronucleatum.     

THE CHARACTERS OF SOME COLIFORM BACTERIA ISOLATED FROM GRASS AND GRASS SILAGE

The species of coliform bacterium predominant on fresh grass was found to be a capsulated type growing well at 30^o C. but unable to grow at 37^o C. For this reason it will not be detected by the presumptive test in bile salt-lactose broth at 37^o C. The name Bacillus (Aerebacter) aerogenes graminis is proposed for this species.
It is possible that conforms of the above type contribute to a small extent to the initial fermentation of the silage. Those coliforms giving the presumptive test at 37^o C. were found in such small numbers in the silage investigated that their influence was concluded to be negligible.
This work forms part of some research carried out under grant from the Research Council of Imperial Chemical Industries, Ltd., to whom the authors wish to make due acknowledgement. Valuable help was also received from Dr S. J. Watson, who supplied samples of grass and silage-