Amidation, protein

Significantly, the bio-inorganic and polymer-containing PM nanocomposites showed no significant shift in the protein amide I and II vibration bands, or in the characteristic 567 nm optical absorption band of the retinal chromophore of BR, indicating that the structural and dynamical properties of the membrane-bound... 

SMANCS (Styrere-co-maleic acid/anhydride polymer bound to neocarzinostatin Neocarzinostatin (an antitumor protein) Amide bond between polymer carboxyl and protein amino None N/A SMANCS showed anticancer activity against many tumor cell lines, and had lower IC50 values than five other anticancer agents tested Liver tumors reduced more than 50% after 6 months in human subjects 15, 56, 57... 

The use of infrared is not limited to p structure detection, however. The erythrocyte study reported here clearly illustrates the information available when spectra are taken in D20. Optical changes permit one to estimate the extent and rapidity of proton exchange in proteins and hence to estimate the availability of peptide bonds to water protons as well as the contributions from random coil and a-helical conformations. The results with erythrocytes indicate that about two-thirds to three-fourths of the protein amide groups are freely accessible to water and that most of the protein exists in an open, mostly random, conformation. The fraction of non-exchangeable protons agrees reasonably well with the helical content determined by ORD. 

The plots of the intensities of selected characteristic bands as a function of lateral position (so-called chemical maps) provide information on the amount of the respective molecules or molecular groups in the different morphological structures (Fig. 4.2). The band at 784 cm 1 can be assigned to out-of-plane deformation vibrational modes of the nucleobases cytosine, thymine and uracil and serves as an indicator for the presence of nucleic acids. At 483 cm-1, a C-C-C deformation of carbohydrate polymers such as starch or pectin is present in some of the spectra. To study the distribution of protein compounds, we analysed characteristic signals of the amino acid phenylalanine (1002 cm 1 ring breathe) as well as of the protein amide I band (1651 cm-1) that is brought about by vibrations of the protein backbones. The maximum of the phenylalanine signal co-localizes with a maximum in protein content... 

In their initial studies, Tfayli et al. [33] acquired spectra from an Episkin model. This model is comprised of human adult keratinocytes which produce stratified epidermis following a 13 h culture period. Raman spectra from this model were compared with normal human skin. Significant differences were noted, particularly in spectral features arising from the 850/830 tyr Fermi doublet (which is sensitive to the H-bonding state of the -OH group [34]) and in the protein amide III region. Usable spectra were acquired to a depth of 15-20 pm. 

Protein Amide I/amide II band (cm-1) CD peaks (nm) Specific activity Km y v max... 

This is the fundamental deformation band. It overlaps the protein amide I band. This band can be used to monitor changes in water content in a variety of materials including meats, protein isolates, and starch. 

NH) 1550 Proteins Amide II (secondary amide). Shifts to higher frequency with increasing hydrogen bonding. 

C4. Clarke, D. D., Neidle, A., Sarkar, N. K., and Waelsch, H., Metabolic activity of protein amide groups. Arch. Biochem. Biophys. 71, 277 (1957). 

Also, no evidence exists for the "special" protein amide postulated by Hansch (13). Even though the models are only crude approximations, they provide a basis for the development of hypotheses that can be critically investigated. In addition, an insight is being gained into how herbicides and receptors might interact. 

Cysteine proteases hydrolyze protein amide bonds through formation of a thio-ester bond with an active site cysteine thiol. Cathepsin K is a member of the pa-... 

Figure 7.10 N N ratio of protein amide II band in two Cladophora glomerata cells showing the subcellular distribution of NOs incorporation, (ca. 150pm diameter). Reproduced with permission from Ref [26] Vibrational Spectroscopy.

Keywords Quantum chemical weak H-bonds proteins amides imidazole benzene indole ... 

Notes a) v (CO) ester linkage b) protein amide II band c) C-OH d) mean... 

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