Carbohydrate strain differences

Another interesting feature of carbohydrate metabolism in H. diminuta relates to the contradictory reports of its excretory end-products (Table 5.9). Many factors could have contributed to these inconsistencies, including the use of different definitive hosts (rats of various strains), different intermediate hosts (species or strain of beetle), different experimental and analytical protocols and ages of hosts and parasites (104, 531). A further complication relates to the work of Coles Simpkin (145), who have shown... 

Recently it has been shown that strain differences in helminths may lead to differences in end products. Kolhagen and coworkers [26] found a variation from 30-60% in the production of lactate in different strains of H. diminuta. It has been reported by McManus [27] that carbohydrate metabolism in adult schistosomes may exclusively lead to lactate formation and that homolactate fermentation is not per se essential for generating ATP in these worms. 

O Brien Working with monkeys, Lang and Barthel (16) have shown that the cholesteremic and atherogenic response to dietary carbohydrate is different in different strains of monkey. 

Abstract To understand how membrane-active peptides (MAPs) function in vivo, it is essential to obtain structural information about them in their membrane-bound state. Most biophysical approaches rely on the use of bilayers prepared from synthetic phospholipids, i.e. artificial model membranes. A particularly successful structural method is solid-state NMR, which makes use of macroscopically oriented lipid bilayers to study selectively isotope-labelled peptides. Native biomembranes, however, have a far more complex lipid composition and a significant non-lipidic content (protein and carbohydrate). Model membranes, therefore, are not really adequate to address questions concerning for example the selectivity of these membranolytic peptides against prokaryotic vs eukaryotic cells, their varying activities against different bacterial strains, or other related biological issues. 

During the increase of the heat production rate, the succession of populations was very rapid, the strains isolated at different incubation times never clustered at a similarly high level. The values of index of utilization of small molecules (amino acids, carbohydrates, alcohols) showed a net tendency to decrease and reach a minimum indicating physiological specialization, paralleled by the maximum value of the specific heat dissipation rate q. ... 

An important point which should be re-emphasised in relation to in vitro studies is the now substantial evidence that certain cestodes exist as a complex of intraspecific variants or strains (pp. 97-98). These strains may exhibit considerable quantitative and qualitative differences in carbohydrate metabolism, thereby complicating the interpretation of results. This particular aspect is elaborated on later. Furthermore, there is the additional problem of differing protocols used by independent research workers which can often make in vitro data comparisons difficult. 

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