MICROBIAL CONVERSION OF METHANE INTO POLY-BETA-HYDROXYBUTYRATE (PHB) - GROWTH AND INTRACELLULAR PRODUCT ACCUMULATION IN A TYPE-II METHANOTROPH
MICROBIAL CONVERSION OF METHANE INTO POLY-BETA-HYDROXYBUTYRATE (PHB) - GROWTH AND INTRACELLULAR PRODUCT ACCUMULATION IN A TYPE-II METHANOTROPH
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DOI：
10.1016/0385-6380(86)90118-4
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发表时间：
1986-01-01
期刊：
影响因子：
--
通讯作者：
SUK, JS
中科院分区：
文献类型：
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作者：
ASENJO, JA;SUK, JS
甲烷转化为聚-β-聚氧乙烯的生物化学途径已经分析了II型甲烷氧化菌中的羟基丁酸（PHB），并用于提出细胞生物量和PHB的化学计量方程。研究了小甲基孢囊菌OBBP分批培养中聚羟基丁酸酯（PHB）积累的必要条件。在氮限制培养中，PHB开始积累在下降的生长期和最大速率的PHB形成发生在生长后期和早期稳定期。接种菌龄对细胞内最大聚羟基丁酸水平有影响，随着接种菌龄的增加，最大聚羟基丁酸水平增加。使用70 h接种物，细胞干重的70%。它已被证明，氧气和甲烷的要求是高的，并在系统中的传质造成了很大的压力，这限制了获得高细胞浓度。当使用增加CH 4和O2的传质的条件时，可以产生5g/l的细胞。最后，研究了富集策略，使得细胞在生长期期间更早地开始积累PHB。讨论了增加细胞质量浓度的替代方案。
The biochemical pathways of methane to poly-.beta.-hydroxybutyrate (PHB) in type II methanotrophs have been analyzed and used to propose stoichiometric equations for cell biomass and PHB. Conditions necessary for PHB accumulation in a batch culture of Methylocystis parvus OBBP were studied. In nitrogen limited cultures PHB started accumulating in the declining growth phase and maximum rate of PHB formation occurred during the late growth and early stationary phases. Inoculum age had an effect on maximum level of intracellular PHB, which increased with inoculum age up to ca. 70% of the cell dry weight using a 70 h inoculum. It has been shown that oxygen and methane requirements are high and pose a great stress on the mass transfer in the system; this limits the obtainment of high cell concentrations. When conditions for increased mass transfer of both CH4 and O2 were used, 5 g/l of cells could be produced. Finally an enrichment strategy was investigated so that cells would start accumulating PHB earlier during the growth phase. Alternatives to increase cell mass concentrations are discussed.