有用土壤微生物之分離及其利用　第五報　一種新分離的麩胺酸聚積菌(ATCC 13943)之性質及其醱酵

Isolation of Economic Soil Microbes and Their Utilization. V. Properties of a Newly Isolated Glutamate Accumulating Bacterium (ATCC 13943) and its Fermentation Data.

吳光丞(K. T. WU) ； 王西華(H. H. Wang)

《化學》 50年4期 (1961/12) Pp. 241-248

https://doi.org/10.6623/chem.1961028

摘要

著者等在分離麩胺酸聚積菌之初期，曾注意及土壤微生物的營養羣(nutritional group)與根圈(rhizosphere)土壤之概念。然接從根圈，及排水溝，分離得一種菌株(ATCC13943),經實驗其生理學上、培養上、形態學上之諸種性質，以及與以前所發表過的麩胺酸聚積菌之性質比較，知道著者等所分離得之菌株，確實是新菌株。另經醱酵試驗後，發見在菌數150 x 10^8/ml左右時，有顯著的麩胺酸聚積之現象。此現象聽著者以前所得之結果，即(1)菌數100 x 10^8/ml以下時，菌數越多麩胺酸之聚積量亦愈多，(2)顯著聚積麩胺酸時，該菌株呈coryneform妝，(3)製造種母培養液(inoculum)時，若菌數在200 x 10^8/ml以上，則麩胺酸之聚積量並不多，完全符合。另外此等結果也與著者之一，所曾提出過之麩胺酸聚積機構相符合。

並列摘要

At the beginning of the isolation of glutamate accumulating bacteria the authors paid much attention to the concept of nutritional group of soil microorganisms and also the concept of rhizosphere where larger microbial population has been founds. Then they started to isolate the economic bacteria with rhizosphere soils and sew, ages which were rich in organic accessory facters, In the course of the isolation they obtained an isolate which has been used for commercial production of mono-sodium glutamate and was registered in American Type Culture Collection. The accession number is 13943. The present paper is aimed to show some characters of the isolate (Table 2) and to prove that the isolate is different from the others^(1, 2,11, 12,13). This paper al so gives the fermentation data of the isolate and discusses the proposed mechanism of bacterial accumulation of glutamate^9. (1) Comparisons made with other isolates^(1 , 2, 11, 12,13) for their physiological cultural and morphological characters are given in Tables 5, 6, 7, 8 and 9. From the results of these tables it is established definitely that the present isolate, ATCC 13943, is different from the others, particularly with respect to the physiological character. In addition, the cytochemical studies of the present isolate'! showed that the isolate has pleomorphism and a life cycle similar to that discussed by Kinoshita on the isolates of Kinoshitat^1, Su^(12), Chen^(13) and Shin-Shin group＂, Therefore the previous conclusion^(14) was drawn again that it ' remained a question whether these isolates (including the present one) are of the same species. At least a detailed serological test is essential for a final decision on taxonomy. (2) It is clear that the cell population around 150 X 10^8 per ml or not so far from this value seems to be ideal for glutamate accumulation (Tables 3 and 4). The previous paper＂ showed that, when the population is below 100 x 10^8 per ml, the larger the population, the more glutamate was accumulated. It has been experienced by the authors during the preparation of the inoculum that, when the inoculum indicated more than 200 x 10^8/ml of the population, less glutamate was accumulated in the inoculum. Cytochemical studies on the isolate^(14 indicated that incomplete division (as coryneform) was found during the stage of glutamate accumulation. Therefore it seems sound to say that the fermentation data given in Tables 3 & 4 can explain the proposed mechanism＂ probably involved in bacterial glutamate accumulation; that is, at a certain narrow range of bacterial population, which is reached by adjusting the nutritional environments, the cultural condition controls the growth and biosynthesis of bacterial bodies. Only at this range, the bacteria accumulate glutamate as the major product in fermentation beers.