Growth of Graphium sp. on natural gas

1969 ◽  
Vol 15 (10) ◽  
pp. 1231-1236 ◽  
Author(s):  
J. E. Zajic ◽  
B. Volesky ◽  
Angela Wellman
Keyword(s):  
Carbon Source ◽  
Natural Gas ◽  
Continuous Culture ◽  
Mixed Culture ◽  
Continuous Cultivation ◽  
Dry Weight ◽  
Mineral Salts ◽  
Ambient Temperatures ◽  
Acid Tolerant ◽  
Enrichment Techniques

A fungus which grows well on a mineral salts solution with natural gas as the carbon source is described and provisionally identified as a Graphium species. Its taxonomic relation to several genera is presented. This organism was isolated from sewage after selection by enrichment techniques and continuous culture. The fermentor was operated at ambient temperatures, 28 °C ± 2, at a volume of 10 liters with a dilution rate of 10 liters/4 days to 10 liters/1.7 days. Coty's mineral salts medium gave the highest tissue yield. When the pH of the incoming mineral salts medium was decreased stepwise from 7.0 to 5.0 the pH of the reactor became self-adjusting, varying from around 2.7 to 3.5, and the dry weight of microbial tissue obtained varied from 65 to 275 mg/h. Also present in the continuous culture was an acid tolerant bacterium, which, when isolated, grew well on natural gas, methanol, and ethanol, and a strain of Trichoderma, which, when isolated, did not use natural gas as a carbon source. In mixed culture the Trichoderma is thought to grow on metabolites produced by either or both the Graphium and the acid-tolerant bacterium during oxidation of natural gas. The nature of the relationship is being investigated. The mixed culture has been under continuous cultivation for 18 months.

scholarly journals Employing a Recombinant Strain of Advenella mimigardefordensis for Biotechnical Production of Homopolythioesters from 3,3′-Dithiodipropionic Acid

2012 ◽  
Vol 78 (9) ◽  
pp. 3286-3297 ◽  
Author(s):  
Yongzhen Xia ◽  
Jan Hendrik Wübbeler ◽  
Qingsheng Qi ◽  
Alexander Steinbüchel
Keyword(s):  
Carbon Source ◽  
Dry Weight ◽  
Pha Synthase ◽  
Mineral Salts ◽  
Content Type ◽  
Genes Encoding ◽  
Polyhydroxyalkanoate Synthase ◽  
Encoding Gene ◽  
Different Origins ◽  
Severe Growth

ABSTRACTAdvenella mimigardefordensisstrain DPN7Twas genetically modified to produce poly(3-mercaptopropionic acid) (PMP) homopolymer by exploiting the recently unraveled process of 3,3′-dithiodipropionic acid (DTDP) catabolism. Production was achieved by systematically engineering the metabolism of this strain as follows: (i) deletion of its inherent 3MP dioxygenase-encoding gene (mdo), (ii) introduction of thebuk-ptboperon (genes encoding the butyrate kinase, Buk, and the phosphotransbutyrylase, Ptb, fromClostridium acetobutylicum), and (iii) overexpression of its own polyhydroxyalkanoate synthase (phaCAm). These measures yielded the potent PMP production strainA. mimigardefordensisstrain SHX22. The deletion ofmdowas required for adequate synthesis of PMP due to the resulting accumulation of 3MP during utilization of DTDP. Overexpression of the plasmid-bornebuk-ptboperon caused a severe growth repression. This effect was overcome by inserting this operon into the genome. Polyhydroxyalkanoate (PHA) synthases from different origins were compared. The native PHA synthase ofA. mimigardefordensis(phaCAm) was obviously the best choice to establish homopolythioester production in this strain. In addition, the cultivation conditions, including an appropriate provision of the carbon source, were further optimized to enhance PMP production. The engineered strain accumulated PMP up to approximately 25% (wt/wt) of the cell dry weight when cultivated in mineral salts medium containing glycerol as the carbon source in addition to DTDP as the sulfur-providing precursor. According to our knowledge, this is the first report of PMP homopolymer production by a metabolically engineered bacterium using DTDP, which is nontoxic, as the precursor substrate.

DECOMPOSITION OF 2,2-DICHLOROPROPIONIC ACID BY SOIL BACTERIA

1959 ◽  
Vol 5 (3) ◽  
pp. 255-260 ◽  
Author(s):  
Lyman A. Magee ◽  
Arthur R. Colmer
Keyword(s):  
Carbon Source ◽  
Liquid Medium ◽  
Soil Bacteria ◽  
Sole Carbon Source ◽  
Solid Medium ◽  
Chloride Ion ◽  
Inhibitory Effect ◽  
Mineral Salts ◽  
Selective Media ◽  
Enrichment Techniques

Eight bacteria capable of decomposing 2,2-dichloropropionate (dalapon) were isolated from soil by means of enrichment techniques and selective media. The decomposition was demonstrated by the clearing of a solid medium containing mineral salts, dalapon, and CaCO3; by a lowering of the pH of a liquid medium containing dalapon as the carbon source; by the increase in chloride ion in the liquid medium; and by the consumption of oxygen by three of the isolates when dalapon was the sole carbon source. Six of these were tentatively classified as Agrobacterium and two were tentatively classified as Pseudomonas, although there was much overlapping of characteristics. These organisms and many unidentified actinomycetes, molds, and bacteria, including a Micrococcus species, overcame the inhibitory effect of dalapon on an agar-decomposing bacterium when grown on the same plate.

Preferential utilization of the methane component of natural gas by a mixed culture of bacteria

1969 ◽  
Vol 15 (9) ◽  
pp. 1114-1116 ◽  
Author(s):  
J. C. Mueller
Keyword(s):  
Carbon Source ◽  
Natural Gas ◽  
Mixed Culture ◽  
Selective Enrichment ◽  
Preferential Utilization

A mixed culture of bacteria was grown on natural gas for 6 months. When tested at this time, the culture was found to use methane as the preferred carbon source. No selective enrichment of ethane or propane utilizers was observed.

scholarly journals Chromochloris zofingiensis (Chlorophyceae) Divides by Consecutive Multiple Fission Cell-Cycle under Batch and Continuous Cultivation

Biology ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 157
Author(s):  
Idan Koren ◽  
Sammy Boussiba ◽  
Inna Khozin-Goldberg ◽  
Aliza Zarka
Keyword(s):  
Cell Cycle ◽  
Continuous Culture ◽  
Continuous Cultivation ◽  
High Light ◽  
Nuclear Transformation ◽  
Storage Lipids ◽  
Microalgal Culture ◽  
Multiple Fission ◽  
Cell Release ◽  
Chromochloris Zofingiensis

Several green algae can divide by multiple fission and spontaneously synchronize their cell cycle with the available light regime. The yields that can be obtained from a microalgal culture are directly affected by cell cycle events. Chromochloris zofingiensis is considered as one of the most promising microalgae for biotechnological applications due to its fast growth and the flexible trophic capabilities. It is intensively investigated in the context of bio-commodities production (carotenoids, storage lipids); however, the pattern of cell-cycle events under common cultivation strategies was not yet characterized for C. zofingiensis. In this study, we have employed fluorescence microscopy to characterize the basic cell-cycle dynamics under batch and continuous modes of phototrophic C. zofingiensis cultivation. Staining with SYBR green—applied in DMSO solution—enabled, for the first time, the clear and simple visualization of polynuclear stages in this microalga. Accordingly, we concluded that C. zofingiensis divides by a consecutive pattern of multiple fission, whereby it spontaneously synchronizes growth and cell division according to the available illumination regime. In high-light continuous culture or low-light batch culture, C. zofingiensis cell-cycle was completed within several light-dark (L/D) cycles (14 h/10 h); however, cell divisions were synchronized with the dark periods only in the high-light continuous culture. In both modes of cultivation, daughter cell release was mainly facilitated by division of 8 and 16-polynuclear cells. The results of this study are of both fundamental and applied science significance and are also important for the development of an efficient nuclear transformation system for C. zofingiensis.

scholarly journals Isolation and Characterization of a Mutant of the Marine Bacterium Alcanivorax borkumensis SK2 Defective in Lipid Biosynthesis

2010 ◽  
Vol 76 (9) ◽  
pp. 2884-2894 ◽  
Author(s):  
Efraín Manilla-Pérez ◽  
Alvin Brian Lange ◽  
Stephan Hetzler ◽  
Marc Wältermann ◽  
Rainer Kalscheuer ◽  
...  
Keyword(s):  
Carbon Source ◽  
Sole Carbon Source ◽  
Marine Bacterium ◽  
Neutral Lipids ◽  
Nile Red ◽  
Dry Weight ◽  
Wax Ester ◽  
Gene Encoding ◽  
Isolation And Characterization ◽  
Key Enzyme

ABSTRACT In many microorganisms, the key enzyme responsible for catalyzing the last step in triacylglycerol (TAG) and wax ester (WE) biosynthesis is an unspecific acyltransferase which is also referred to as wax ester synthase/acyl coenzyme A (acyl-CoA):diacylglycerol acyltransferase (WS/DGAT; AtfA). The importance and function of two AtfA homologues (AtfA1 and AtfA2) in the biosynthesis of TAGs and WEs in the hydrocarbon-degrading marine bacterium Alcanivorax borkumensis SK2 have been described recently. However, after the disruption of both the AtfA1 and AtfA2 genes, reduced but substantial accumulation of TAGs was still observed, indicating the existence of an alternative TAG biosynthesis pathway. In this study, transposon-induced mutagenesis was applied to an atfA1 atfA2 double mutant to screen for A. borkumensis mutants totally defective in biosynthesis of neutral lipids in order to identify additional enzymes involved in the biosynthesis of these lipids. At the same time, we have searched for a totally TAG-negative mutant in order to study the function of TAGs in A. borkumensis. Thirteen fluorescence-negative mutants were identified on Nile red ONR7a agar plates and analyzed for their abilities to synthesize lipids. Among these, mutant 2 M131 was no longer able to synthesize and accumulate TAGs if pyruvate was used as the sole carbon source. The transposon insertion was localized in a gene encoding a putative cytochrome c family protein (ABO_1185). Growth and TAG accumulation experiments showed that the disruption of this gene resulted in the absence of TAGs in 2 M131 but that growth was not affected. In cells of A. borkumensis SK2 grown on pyruvate as the sole carbon source, TAGs represented about 11% of the dry weight of the cells, while in the mutant 2 M131, TAGs were not detected by thin-layer and gas chromatography analyses. Starvation and lipid mobilization experiments revealed that the lipids play an important role in the survival of the cells. The function of neutral lipids in A. borkumensis SK2 is discussed.

Statistical Analysis of Growth and Amylase Production by Aspergillus flavus grown on Different Carbon Sources

2013 ◽  
Vol 2 (1) ◽  
Author(s):  
M O Oyewale
Keyword(s):  
Carbon Source ◽  
Aspergillus Flavus ◽  
Amylase Activity ◽  
Carbon Sources ◽  
Dry Weight ◽  
Soluble Starch ◽  
Optimum Growth ◽  
Amylase Production ◽  
Level Of Significance ◽  
Cassava Peel

The mycelial dry weight and dinitrosalicylic acid (D.N.S.A.) method was used to determine growth and amylase production by Aspergillus flavus grown on different carbon sources. Growth of the fungus was determined at 24 h intervals over a period of six days by the dry mycelial weight methods, while the amylase activity in the culture filtrates of A. flavus was determined by the D.N.S.A method. A total of 45 samples were prepared to determine growth and amylase activity of Aspergillus flavus grown on different carbon sources. The concentration of the various carbon sources ranges between 0.4 to 2% W/V. Duncan’s multiple range test was used to determine the level of significance of the different carbon sources for effective growth and amylase production by Aspergillus flavus. Aspergillus flavus demonstrated the capability to produce significant growth and amylase activities in the medium containing soluble starch, sorghum and cassava peel as sole carbon source. The amount of mycelial dry weight produced from soluble starch, sorghum and cassava peel is significantly higher than those produced from other carbon sources. The data revealed that there is a correlation between growth and amylase production by Aspergillus flavus. The available data from this study showed that soluble starch is the best carbon source for optimum growth and amylase production by A flavus while sorghum and cassava peel are close substitute for optimum growth and amylase production by Aspergillus flavus. Keywords: Growth, amylase activity and Aspergillus flavus

scholarly journals Comparisons between continuous and batch processing to produce clavulanic acid by Streptomyces clavuligerus

2005 ◽  
Vol 48 (spe) ◽  
pp. 97-104 ◽  
Author(s):  
Álvaro Baptista-Neto ◽  
Juliana Conceição Teodoro ◽  
Luiz Claudio Macedo Cassiano Filho ◽  
Alberto Colli Badino ◽  
Carlos Osamu Hokka
Keyword(s):  
Continuous Culture ◽  
Hollow Fiber ◽  
Cell Concentration ◽  
Continuous Cultivation ◽  
Batch Process ◽  
Streptomyces Clavuligerus ◽  
High Cell ◽  
Continuous Cultures ◽  
High Cell Concentration ◽  
Cell Recycling

The aim of the present work was to compare CA production in continuous culture with and without cell recycling and in batch process by Streptomyces clavuligerus. Continuous cultivations with high cell concentration using cell recycling were performed utilizing a hollow fiber ultrafiltration module to separate cells from the filtrate broth. The continuous cultures without cell recycling and the batch cultivations were performed conventionally. The highest productivity was attained in the continuous cultivation with cell recycling (22.2 mg.L-1.h-1). The highest CA concentration was obtained in the batch process (470 mg.L-1.h-1).

scholarly journals Effect of Lactose on Soluble-glucan Production and on the Ultrastructure of Sclerotium rolfsii Sacc. Grown in Submerged Culture

Microbiology ◽  
2000 ◽  
Vol 81 (1) ◽  
pp. 145-149 ◽  
Author(s):  
Y. Okon ◽  
I. Chet ◽  
Naomi Kislev ◽  
Y. Henis
Keyword(s):  
Carbon Source ◽  
Submerged Culture ◽  
Sole Carbon Source ◽  
Synthetic Medium ◽  
Sclerotium Rolfsii ◽  
Dry Weight ◽  
Solid Media

SUMMARY A significant increase in mycelial dry weight and a decrease in production of extracellular glucan were observed when lactose was added to a submerged culture of Sclerotium rolfsii grown in a liquid glucose-synthetic medium. When added as a sole carbon source, lactose at 2·5% (w/v) induced the formation of dark, spherical, compact bodies. The ultrastructure of these bodies is compared with that of sclerotia formed on solid media.

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