Baron E S, Saz A K
J Clin Microbiol. 1976 Mar;3(3):330-3. doi: 10.1128/jcm.3.3.330-333.1976.
Typical gonococci metabolize glucose; however, occasional strains of Neisseria gonorrhoeae fail to metabolize glucose when tested on cystine Trypticase agar (CTA) medium, a fact that leads to delay in identification. Certain strains of so-called glucose-negative N. gonorrhoeae do indeed metabolize glucose, depending on the medium used in testing for metabolism of the carbohydrate. Six strains were tested that failed to oxidize glucose with the production of acid when tested on standard CTA medium, yet all produced acid from glucose when supplemented GC medium with a phenol red indicator was utilized. An attempt was made to single out the compound present in CTA that leads to inhibition of metabolism and, occasionally, growth as well. We found that certain ratios of the cystine and Na2SO3 concentrations are inhibitory, including that ratio of the two compounds present in CTA medium; however, L-cysteine, when included in similar concentrations, did not inhibit the metabolic reaction.
典型的淋球菌能代谢葡萄糖；然而，在胱氨酸胰蛋白酶琼脂（CTA）培养基上进行检测时，偶尔会有淋病奈瑟菌菌株无法代谢葡萄糖，这一事实导致鉴定延迟。某些所谓的葡萄糖阴性淋病奈瑟菌菌株实际上确实能代谢葡萄糖，这取决于用于检测碳水化合物代谢的培养基。测试了六株菌株，它们在标准CTA培养基上测试时不能氧化葡萄糖产酸，但当使用添加了酚红指示剂的GC培养基时，所有菌株都能从葡萄糖产酸。人们试图找出CTA中导致代谢抑制以及偶尔也会导致生长抑制的化合物。我们发现，胱氨酸和亚硫酸钠浓度的某些比例具有抑制作用，包括CTA培养基中这两种化合物的比例；然而，当L-半胱氨酸以相似浓度存在时，并不抑制代谢反应。
