Leggate J, Holms W H
J Bacteriol. 1968 Dec;96(6):2110-7. doi: 10.1128/jb.96.6.2110-2117.1968.
The synthesis of beta-lactamase in response to 2-(2'-carboxyphenyl)-benzoyl-6-aminopenicillanic acid as inducer was studied in Staphylococcus aureus. The inducer was not detectably hydrolyzed by beta-lactamase and had minimal antibacterial activity. The kinetics of induction showed a lag of 4 to 6 min in a nutrient broth medium and 8 to 12 min in a defined medium, followed by constant differential rates of synthesis of beta-lactamase. The differential rate of beta-lactamase synthesis in nutrient broth was unaltered by supplementing the medium with glucose, galactose, lactose, arabinose, glycerol, or sucrose. Variations in the partial pressure of oxygen did not alter the differential rate of synthesis of beta-lactamase over the range 18 to 50% oxygen in nitrogen. Even when the rate of growth was considerably reduced by high-oxygen tension, the differential rate of synthesis of the enzyme remained the same. The differential rate of beta-lactamase synthesis at low inducer concentration increased after a shift down in growth rate. The effect was observed with several inducers and under different nutritional conditions, but was always preceded by a change in growth rate. It is suggested that the change in growth rate itself causes the increase in differential rate of beta-lactamase synthesis.
在金黄色葡萄球菌中研究了响应于2-(2'-羧基苯基)-苯甲酰基-6-氨基青霉烷酸作为诱导剂时β-内酰胺酶的合成。该诱导剂未被β-内酰胺酶显著水解且抗菌活性极小。诱导动力学显示，在营养肉汤培养基中延迟4至6分钟，在限定培养基中延迟8至12分钟，随后β-内酰胺酶的合成速率恒定。在营养肉汤中补充葡萄糖、半乳糖、乳糖、阿拉伯糖、甘油或蔗糖不会改变β-内酰胺酶的合成速率。在氮气中氧气分压在18%至50%范围内变化时，不会改变β-内酰胺酶的合成速率。即使高氧张力使生长速率显著降低，该酶的合成速率仍保持不变。在生长速率下降后，低诱导剂浓度下β-内酰胺酶的合成速率增加。在几种诱导剂和不同营养条件下均观察到该效应，但总是在生长速率改变之前出现。有人提出，生长速率的改变本身会导致β-内酰胺酶合成速率的增加。
