Biochemical fractionation

Table 11.2. Model calculations of weighting functions for fractionation of carbon isotope ratios (in %o) from dietary nutrient biochemical fractions to tissue biochemical fractions.

Immunoelectron microscopic and biochemical fractionation data on specific processing enzymes have permitted the localization of specific processing steps in the processing pathway for proteins in the Golgi complex. The distribution of many remaining enzymes and steps has not yet been determined. The distribution for each step indicated in this table reflects a significant enrichment rather than an exclusive localization. 

The next major step was the development of an assay to determine the functional identity of the deduced PDesat-TnAllZ desaturase. Initial efforts to develop an in vitro reconstitutive biochemical assay combined the recombinant PDesat-TnAllZ protein purified from E. coli with phospholipids and a biochemical fraction from beef liver containing cytochrome b5 reductase and cytochrome b5. These efforts were unsuccessful (Knipple and Roelofs, unpublished). 

Sequential extractions with various solvents have been used to isolate discrete biochemical fractions and to investigate the biochemical associations of Se in marine animals and seaweeds [30, 32, 37]. Figure 20.4 presents an overall flow chart of extraction and separation procedures that can be used to isolate, separate,... 

Fi/Fo ATPase or other highly abundant mitochondrial proteins, in addition to other unexpected proteins from other subcellular locations. Of course, it is likely that no one actually looked for such proteins in rafts before and with the unbiased nature of proteomics one expects (or even hopes ) to find components that had not been previously described. However, any analysis of a biochemical fraction can only be as good as the initial preparation of that fraction and in previous lipid raft studies the minimum standard one has to meet to claim a protein is in rafts is to demonstrate sensitivity to cholesterol disruption. 

EGFR (epidermal growth factor receptor) Plasma membrane At nuclear membrane by biochemical fractionization M. Musculus liver Yes (Schirmer et al. 2003 Klein et al. 2004)... 

Atypical type IV P-type ATPase PM, post-mitochondrial supernatant Immunoelectron microscopy and biochemical fractionization O.cuniculus endometrium Other family members were identified, but not this variant (Mansharamani et al. 2001)... 

Thor, P., Cervetto, G., Besiktepe, S., Ribera-Maycas, E., Tang, K. W., and Dam, H. G. (2002). Influence of two different green algal diets on specific dynamic action and incorporation of carbon into biochemical fractions in the copepod Acartia tonsa.J. Plankton Res. 24(4), 293—300. 

The biochemical fractions of the serum alkaline phosphatase in cirrhosis are listed in Table 13 according to blood types A and 0. It may be advantageous to compare the various moieties in these patients with the data on normal subjects of corresponding blood type (Table 10). In some cases (4, 5, 14) the elevation is proportionate in the LPSAP and non-LPSAP moieties, whereas in others (1, 2, 3, 9, 10, 12, 13, 15) there is a disproportionate elevation in the LPSAP fraction. Subject 7 exhibits the largest contribution of LPSAP (60%). There appears to be no similarity of the heat sensitivities of LPSAP and non-LPSAP in subjects 4, 5, 7, 14, and 15 with total LPSAP hyperphosphatasemia. In fact, the relatively high heat inactivation of sera 5, 6, 7, and 12 would register negatively for liver in a heat-inactivation test of total alkaline phosphatase (P19). 

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