Höltje J V
Max-Planck-Institut für Entwicklungsbiologie, Abteilung Biochemie, Tübingen, Germany.
EXS. 1996;75:105-10. doi: 10.1007/978-3-0348-9225-4_7.
The natural substrate of lysozyme is the rigid layer of bacterial cell walls, the murein (peptidoglycan), which is a gigantic polymer of (GlcNAc-MurNAc)n polysaccharide strands crosslinked through short peptide bridges at the lactyl groups of the muramic acid residues. Thus, lysozyme lyses bacteria by degrading their protective exoskeleton, the murein sacculus. The high molecular weight murein is thereby hydrolysed to low molecular weight muropeptides, a process that can be followed quantitatively by different methods. However, due to the insolubility of the murein sacculus, the enzyme kinetics are rather complex. Therefore, a variety of different low molecular weight substrates have been prepared, both murein degradation products and synthetic compounds. These substrates allow a better characterization of the binding and catalytic mechanism of lysozyme. In addition, they are used in various photometric, isotopic and immunological lysozyme assays.
溶菌酶的天然底物是细菌细胞壁的刚性层，即胞壁质（肽聚糖），它是一种巨大的（GlcNAc-MurNAc）n多糖链聚合物，通过短肽桥在胞壁酸残基的乳酰基处交联。因此，溶菌酶通过降解细菌的保护性外骨骼——胞壁质囊来裂解细菌。高分子量的胞壁质由此被水解为低分子量的胞壁肽，这一过程可以通过不同方法进行定量跟踪。然而，由于胞壁质囊不溶，酶动力学相当复杂。因此，人们制备了多种不同的低分子量底物，包括胞壁质降解产物和合成化合物。这些底物有助于更好地表征溶菌酶的结合和催化机制。此外，它们还用于各种光度法、同位素法和免疫法溶菌酶测定。
