Lysozyme identification

Aldrich, J.E., Cundall, RB., Adams, G.E. and Willson, RL. (1969). Identification of essential residues in lysozyme a pulse radiolysis method. Nature 221, 1049-1051. 

Figure 6 Separation of basic proteins on an untreated fused silica capillary with diaminopropane as buffer additive. Capillary 75 cm (55 cm to detector) x 50 p i.d. Buffer pHs are as noted on the figure with 30 to 60 mM DAP as an additive 200 to 240 V/cm peak identification 1 = lysozyme, 2 = cytochrome, 3 = ribonuclease, 4 = a-chymotrypsin 5 = trypsinogen, 6 = r-huIL-4. (From Bullock, J. A. and Yuan, L.-C., /. Microcol. Sep., 3, 241, 1991. With permission.)...

Hough, R., Pratt, G., and Rechsteiner, M. (1986). Ubiquitin-lysozyme conjugates. Identification and characterization of an ATP-dependent protease from rabbit reticulocyte lysates. J. Biol. Chem. 261,2400-2408. 

Gel Electrophoresis This method was used in the determination of the purity of native lysozyme and identification of ozonized products. Different gel concentrations (7,8,9,10%) and buffer solutions (0.25M borate, pH 8.7 0.025M phosphate, pH 7.1) were tried and the best results were obtained with 7% gel in pH 8.7 buffer. 

Aliphatic hydroxyl groups cannot normally be selectively modified except in certain special cases such as the serine proteinases. In anhydrous formic acid, the A,O-acyl migration that occurs in strong sulfuric or phosphoric acid apparently does not occur. Instead there is formylation of the serine and threonine residues (208). Enzymically inactive aggregates are produced, but the reaction is reversed in aqueous solution at neutral pH and the activity returns. Josefsson reported the introduction of 29 formyl groups in RNase (209) as compared to the total of 25 Ser and Thr residues. This identification of reaction sites is not clear, however, since the number of formyl groups introduced into lysozyme far exceeded the Ser-Thr total. 

Figure 10.8. Gene identification by Procrustes. The nucleotide sequence encoding human lysozyme is used as a query sequence to identify its gene structure against known protein sequence (i.e., pig lysozyme protein). The output includes sequence aignment of the source (predicted translate) versus target protein (pig lysozyme).

Figure 10.11. Outputs from FGENESH and FGENE of GeneFinder. The nucleotide sequence of DNA encoding human lysozyme (5648 bp) is submitted to Sanger Centre for gene identification with FGenesh (hidden Markov model) and Fgene (pattern recognition) tools. The identical translate is predicted by the two programs.

Fig. 10.19. Electrochromatogram of protein separation on a diol. Conditions pH 4.14, capillary 450 mm x 50 pm i.d., 250 mm packed length. Peak identification 1, cytochrome c 2, lysozyme 3, myoglobin 4, ribonuclease A. Reproduced with permission from Pesek et al. [102].

Moreira IS, Fernandes PA, Ramos MJ (2006) Hot spots computational identification — application to the complex formed between the hen egg-white lysozyme (HEL) and the antibody HyHEL-10, Int J Quantum Chem, 107 299-310... 

Although the resultant electron density maps (Smith et ai, 1987) did not enable a high resolution of structure, the overall features of the models of Browne et al. (1969) and Warme et al. (1974) were confirmed. Also, the identification of helix B (residues 24—36 in hen egg white lysozyme) in a-lactalbumin enabled resolution of a problem found in the... 

Since epoxides potentially will react with a variety of amino acids, many products may be formed if they are incorporated into affinity labels. However at present affinity labels containing epoxides have been shown to modify either glutamate or aspartate residues in pepsin, lysozyme, those phosphate isomerase and j -glucosidase. The only other residue which has as yet been modified by epoxides is methionine 192 of chymotrypsin. In general, the other possible products should be similar in stability to derivatives formed by haloketones. Therefore the methods for identification of the amino acid derivatives formed by reaction with epoxides closely parallel those described in connection with haloketones ( 5.3.2). 

Analysis of in vivo-formed pellicle by a combination of electrophoretic separation and MALDI-TOF showed the presence of intact histatin 1, cystatin SN, statherin, lysozyme, albumin and amylase [15, 39], In addition, intact cytokeratins 13 and 15 and calgranulin B were identified as components of the salivary pellicle layer for the first time using MALDI-TOF mass spectrometry [15]. Calgranulin B has been shown to be a component of saliva and gingival crevicular fluid [15]. The identification of cytokeratins in the salivary pellicle layer points to the oral epithelium as one of the sources of proteins adsorbed on the tooth surface. 

Sachsenheimer and Schulz report the structure of another crystalline form of adenylate kinase which appears to be related to the previously known form by a conformation change in a segment. The binding sites of ATP and AMP to this enzyme were also located. Similar work on the identification of binding sites and the assessment of conformational changes has been continued with ribo-nuclease, alcohol dehydrogenase, concanavalin A, " hexokinase, lysozyme," flavodoxin, and oxy-erythrocrurin." ... 

Brink (1992) described a laboratory experiment for the qualitative analysis of amino acids present in egg lysozyme, involving hydrolysis with HCl, dansyla-tion, and amino acid identification by TLC. The C-terminal amino acid was identified as leucine in a second experiment in which lysozyme was oxidized with acetic acid, hydrolyzed with carboxypeptidase A, and the cleaved acid dansylated and identified by TLC. 

The identification and characterization of lysozyme from the haemolymph of the soft-shelled clam (Mya arenaria) have been reported. ... 

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