Elliott T S, Ward J B, Rogers H J
J Bacteriol. 1975 Nov;124(2):623-32. doi: 10.1128/jb.124.2.623-632.1975.
The biosynthesis of peptidoglycan and teichoic acid by reverting protoplasts of Bacillus licheniformis 6346 His-, in cubated at 35 C on medium containing 2.5% agar, is detectable after 40 min. The amount of N-acetyl-[1-14C]glucosamine incorporated into peptidoglycan and teichoic acid on continued incubation doubles at the same rate as the incorporation of [3H]tryptophan into protein. At the early stages of reversion the average glycan chain length, measured by the ratio of free reducing groups of muramic acid and glucosamine to total muramic acid present, is very short. As reversion proceeds, the average chain length increases to a value similar to the found in the wall of the parent bacillus. The extent of cross-linkage found in the peptide side chains of the peptidoglycan also increases as reversion proceeds. At the completion of reversion the wall material synthesized has similar characteristics to those of the walls of the parent bacilli, containing peptidoglycan and teichoic and teichuronic acids in about the same proportions. Soluble peptidoglycan can be isolated from the reversion medium, amounting to 30% of the total formed after 3 h of incubation and 8% after 12 h. This amount was reduced by the presence in the medium of the walls of an autolysin-deficient mutant; they were not formed at all by reverting protoplasts of the autolysin-deficient mutant itself. Analysis of the soluble material provided additional evidence for their being autolytic products rather than small unchanged molecules. When protoplasts were incubated on medium containing only 0.8% agar, 53 to 67% of the peptidoglycan formed after 3 h of incubation was soluble, and 21% after 12 h. Fibers that appeared to be sheared from the protoplasts at intermediate stages of reversion on medium containing 2.5% agar were similar in composition to the bacillary walls.
地衣芽孢杆菌6346 His-回复原生质体在含2.5%琼脂的培养基上于35℃培养时，40分钟后可检测到肽聚糖和磷壁酸的生物合成。继续培养时，掺入肽聚糖和磷壁酸中的N-乙酰-[1-14C]葡萄糖胺的量与掺入蛋白质中的[3H]色氨酸的量以相同速率翻倍。在回复的早期阶段，通过胞壁酸和葡萄糖胺的游离还原基团与存在的总胞壁酸的比率测量的平均聚糖链长度非常短。随着回复过程的进行，平均链长度增加到与亲本芽孢杆菌细胞壁中发现的值相似。随着回复过程的进行，在肽聚糖的肽侧链中发现的交联程度也增加。回复完成时，合成的壁物质具有与亲本芽孢杆菌细胞壁相似的特征，含有比例大致相同的肽聚糖、磷壁酸和磷壁醛酸。可从回复培养基中分离出可溶性肽聚糖，孵育3小时后占总形成量的30%，12小时后占8%。培养基中自溶素缺陷型突变体的细胞壁会减少该量；自溶素缺陷型突变体自身的回复原生质体根本不会形成。对可溶性物质的分析为它们是自溶产物而非未改变的小分子提供了额外证据。当原生质体在仅含0.8%琼脂的培养基上孵育时，孵育3小时后形成的肽聚糖有53%至67%是可溶的，12小时后为21%。在含2.5%琼脂的培养基上回复中间阶段似乎从原生质体剪切下来的纤维在组成上与杆菌细胞壁相似。
