Iacono V J, MacKay B J, DiRienzo S, Pollock J J
Infect Immun. 1980 Aug;29(2):623-32. doi: 10.1128/iai.29.2.623-632.1980.
The antibacterial properties of lysozyme were investigated with oral microorganisms representing the seven serotypes (a through g) of Streptococcus mutans, Veillonella alcalescens, and the virulent (V) and avirulent (AV) strains of Actinomyces viscosus T14. Growth of bacteria in defined medium was monitored spectrophotometrically after the addition of various amounts (25 mug to 5 mg/ml) of enzyme. No growth inhibition of V. alcalescens was observed. Inhibition of A. viscosus T14(V) and A. viscosus T14(AV) occurred with 160 mug of lysozyme per ml. Of the S. mutans cultures tested, the serotype a and b strains were inhibited with as little as 25 mug of enzyme per ml, whereas e and f strains were most resistant to the bacteriostatic activity of lysozyme. The presence of dl-threonine or sucrose in growth medium did not significantly affect the results. A lysoplate assay was developed to rapidly survey the bacterial cultures for their susceptibility to the lytic ability of the enzyme. Lysis, as a measure of a zone of clearing in agarose plates, occurred for all microorganisms in the presence of lysozyme after the subsequent addition of NaCl or detergent. The bactericidal activity of lysozyme was determined on S. mutans BHT and S. mutans LM-7 by the pour plate technique. Preincubation of S. mutans LM-7 with as much as 1 mg of enzyme for 90 min did not affect viability or growth, whereas preincubation of S. mutans BHT with 1 mg of lysozyme resulted in no recoverable colony-forming units. An antigen containing extract of S. mutans LM-7 blocked the growth inhibitory property of lysozyme. Human lysozyme was a more effective antibacterial factor than hen egg white lysozyme. Total growth inhibition of S. mutans BHT was effected with 40 mug of human enzyme, and as little as 10 mug of human enzyme inhibited growth for greater than 20 h. The data presented indicate that different mechanisms may be responsible for the bacteriostatic, lytic, and bactericidal properties of the enzyme and that lysozyme is a selective but effective antibacterial factor for oral microorganisms.
研究了溶菌酶对代表变形链球菌7种血清型（a至g）、产碱韦荣球菌以及粘性放线菌T14的强毒株（V）和无毒株（AV）的口腔微生物的抗菌特性。在添加不同量（25微克至5毫克/毫升）的酶后，用分光光度法监测细菌在限定培养基中的生长情况。未观察到产碱韦荣球菌的生长受到抑制。每毫升160微克的溶菌酶可抑制粘性放线菌T14（V）和粘性放线菌T14（AV）的生长。在所测试的变形链球菌培养物中，血清型a和b菌株每毫升低至25微克的酶即可受到抑制，而e和f菌株对溶菌酶的抑菌活性最具抗性。生长培养基中dl - 苏氨酸或蔗糖的存在对结果没有显著影响。开发了一种溶菌平板测定法，以快速检测细菌培养物对该酶裂解能力的敏感性。在随后添加氯化钠或去污剂后，在溶菌酶存在的情况下，所有微生物在琼脂糖平板上均出现了以透明圈表示的裂解现象。通过倾注平板技术测定了溶菌酶对变形链球菌BHT和变形链球菌LM - 7的杀菌活性。变形链球菌LM - 7与多达1毫克的酶预孵育90分钟对其活力或生长没有影响，而变形链球菌BHT与1毫克溶菌酶预孵育后未检测到可恢复的菌落形成单位。来自变形链球菌LM - 7的含抗原提取物可阻断溶菌酶的生长抑制特性。人溶菌酶是比鸡蛋清溶菌酶更有效的抗菌因子。40微克的人溶菌酶可完全抑制变形链球菌BHT的生长，低至10微克的人溶菌酶可抑制生长超过20小时。所呈现的数据表明，该酶的抑菌、裂解和杀菌特性可能由不同机制引起，并且溶菌酶是一种对口腔微生物具有选择性但有效的抗菌因子。
