scholarly journals Cellulase production by co-culture of Bacillus licheniformis and B. paralicheniformis over monocultures on microcrystalline cellulose and chicken manure-supplemented rice bran media

BioResources ◽  
2021 ◽  
Vol 16 (4) ◽  
pp. 6850-6869
Author(s):  
Muinat Olanike Kazeem ◽  
Kamoldeen A. Ajijolakewu ◽  
Nor’ Aini Abdul Rahman
Keyword(s):  
Rice Bran ◽  
Bacillus Licheniformis ◽  
Microcrystalline Cellulose ◽  
Hydrolysis Product ◽  
Fold Increase ◽  
Cellulase Production ◽  
Chicken Manure ◽  
Bacillus Paralicheniformis ◽  
Metabolic Performance ◽  
Synergistic Behavior

Single cultures and co-cultures of Bacillus licheniformis and Bacillus paralicheniformis isolated from compost were evaluated for their carboxymethyl cellulase (CMCase) and filter paperase (FPase) production potential. Using a medium supplemented with microcrystalline cellulose (MCC), in the co-culture, CMCase and FPase activities increased 8.87- and 2.28-fold and 10.15- and 3.20-fold over B. licheniformis and B. paralicheniformis monocultures, respectively. The synergistic behavior of the two isolates might be due to the consumption of hydrolysis product (glucose, cellobiose) by one or both of the isolates, which improved their metabolic performance for cellulase secretion. Optimal conditions for cellulase production by this co-culture were a temperature of 45 °C, and pH 7 at 180 rpm in a medium containing rice bran at 1% (w/v) and chicken manure as nitrogen supplement at 2% (w/v). The maximum CMCase and FPase produced under the above conditions were 79.8 U/mL and 12.5 U/mL, respectively. This corresponds to 257.4- and 59.5-fold enhancement in CMCase and FPase activity, respectively, over B. licheniformis monoculture, and 306.9- and 83.3-fold increase with respect to the B. paralicheniformis monoculture. These results indicate that improved cellulase production can be achieved through co-culture and chicken manure nitrogen-supplement.

Amplification of LTB4 generation in AM-PMN cocultures: transcellular 5-lipoxygenase metabolism

1991 ◽  
Vol 261 (2) ◽  
pp. L195-L203 ◽  
Author(s):  
F. Grimminger ◽  
U. Sibelius ◽  
W. Seeger
Keyword(s):  
Hydrolysis Product ◽  
Calcium Ionophore ◽  
Fold Increase ◽  
Metabolite Profile ◽  
Product Formation ◽  
Calcium Ionophore A23187 ◽  
Oxidation Products ◽  
Ionophore A23187 ◽  
Lipoxygenase Product ◽  
Isolated Cell

The generation of arachidonic acid (AA) metabolites by human polymorphonuclear leukocytes (PMN) and by rabbit alveolar macrophages (AM) was investigated and compared with that produced under conditions of coculture. Incubation of PMN with the calcium ionophore A23187 resulted in rapid generation of leukotriene (LT) B4 and its omega-oxidation products, paralleled by substantial secretion of 5-hydroxyeicosatetraenoic acid (HETE) and intact LTA4. Rapid LTA4 decay to nonenzymatic hydrolysis products in the extracellular space ensued. Exogenous AA, offered simultaneously with the ionophore, markedly increased 5-lipoxygenase product formation. Incubation of AM with A23187 evoked protracted generation of LTB4 in the absence of omega-oxidation, with concomitant liberation of 5-HETE, 15-HETE, free AA, and minor amounts of AA cyclooxygenase products. Exogenously offered LTA4 was avidly taken up and converted into LTB4 by these cells. Costimulation of AM and PMN with the ionophore resulted in an approximately 2.5-fold increase in the generation of LTB4 and its metabolites (compared with the summed amounts of the isolated cell experiments), whereas 5-HETE and nonenzymatic LTA4, hydrolysis product formation were markedly reduced. This change in metabolite profile was dependent on the AM-to-PMN ratio. Acetylsalicylic acid increased 5-lipoxygenase product formation in the coculture studies but not in the isolated cell experiments. AA prelabeling of either PMN or AM resulted in radioactivity detection in all AA lipoxygenase products except for 15-HETE.(ABSTRACT TRUNCATED AT 250 WORDS)

scholarly journals Use of fusion transcription factors to reprogram cellulase transcription and enable efficient cellulase production in Trichoderma reesei

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Fangzhong Wang ◽  
Ruiqin Zhang ◽  
Lijuan Han ◽  
Wei Guo ◽  
Zhiqiang Du ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Trichoderma Reesei ◽  
Parent Strain ◽  
Fungal Growth ◽  
Biomass Accumulation ◽  
Hyphal Growth ◽  
Fold Increase ◽  
Cellulase Production ◽  
Fungal Species ◽  
New Strategy

Abstract Background Trichoderma reesei is widely used for cellulase production and accepted as an example for cellulase research. Cre1-mediated carbon catabolite repression (CCR) can significantly inhibit the transcription of cellulase genes during cellulase fermentation in T. reesei. Early efforts have been undertaken to modify Cre1 for the release of CCR; however, this approach leads to arrested hyphal growth and decreased biomass accumulation, which negatively affects cellulase production. Results In this study, novel fusion transcription factors (fTFs) were designed to release or attenuate CCR inhibition in cellulase transcription, while Cre1 was left intact to maintain normal hyphal growth. Four designed fTFs were introduced into the T. reesei genome, which generated several transformants, named Kuace3, Kuclr2, Kuace2, and Kuxyr1. No obvious differences in growth were observed between the parent and transformant strains. However, the transcription levels of cel7a, a major cellulase gene, were significantly elevated in all the transformants, particularly in Kuace2 and Kuxyr1, when grown on lactose as a carbon source. This suggested that CCR inhibition was released or attenuated in the transformant strains. The growth of Kuace2 and Kuxyr1 was approximately equivalent to that of the parent strain in fed-batch fermentation process. However, we observed a 3.2- and 2.1-fold increase in the pNPCase titers of the Kuace2 and Kuxyr1 strains, respectively, compared with that of the parent strain. Moreover, we observed a 6.1- and 3.9-fold increase in the pNPCase titers of the Kuace2 and Kuxyr1 strains, respectively, compared with that of Δcre1 strain. Conclusions A new strategy based on fTFs was successfully established in T. reesei to improve cellulase titers without impairing fungal growth. This study will be valuable for lignocellulosic biorefining and for guiding the development of engineering strategies for producing other important biochemical compounds in fungal species.

scholarly journals Betamethasone modulation of sphingomyelin hydrolysis up-regulates CTP:cholinephosphate cytidylyltransferase activity in adult rat lung

1996 ◽  
Vol 318 (1) ◽  
pp. 333-341 ◽  
Author(s):  
Rama K MALLAMPALLI ◽  
Satya N MATHUR ◽  
Lorna J WARNOCK ◽  
Ronald G SALOME ◽  
Gary W HUNNINGHAKE ◽  
...  
Keyword(s):  
Hydrolysis Product ◽  
Fold Increase ◽  
Acid Sphingomyelinase ◽  
Male Rats ◽  
Reversible Inhibitor ◽  
Serine Palmitoyltransferase ◽  
Adult Rat ◽  
Surfactant Synthesis

Glucocorticoids appear to play an integral role in stimulating surfactant synthesis by activating the rate-regulatory enzyme for phosphatidylcholine synthesis, CTP:cholinephosphate cytidylyltransferase (CT). The activity of liver CT, in vitro, has been shown to be inhibited by the sphingomyelin hydrolysis product, sphingosine. In order to investigate the mechanisms by which glucocorticoids alter CT activity, in vivo, we administered betamethasone (1 mg/kg intraperitoneally) sequentially to adult male rats for 5 days. Betamethasone increased CT activity 2-fold relative to control in whole lung. The hormone also increased membrane-bound activity, but did not affect cytosolic enzyme activity. Betamethasone modestly increased CT mRNA as determined by the reverse-transcription PCR and Southern analysis of PCR products, but did not alter the levels of immunoreactive enzyme in lung membranes as demonstrated by Western blotting. The hormone did, however, produce a nearly 3-fold increase in membrane-associated sphingomyelin, and co-ordinately a substantial decrease in the levels of sphingosine in lung membranes. Sphingosine, but not sphinganine, was a competitive, reversible inhibitor of lung CT with respect to the enzyme activator, phosphatidylglycerol. Betamethasone decreased the activities of the sphingomyelin hydrolases: acid sphingomyelinase by 33% and of alkaline ceramidase by 21%. The hormone also inhibited the generation of sphingosine from lysosphingomyelin in lung membranes. There was no significant effect of the hormone on serine palmitoyltransferase activity, the first committed enzyme for sphingolipid biosynthesis. Further, administration of l-cycloserine, an inhibitor of sphingosine formation, was shown to stimulate CT activity by 74% and increase disaturated phosphatidylcholine in alveolar lavage by 52% relative to control. These observations suggest that glucocorticoids up-regulate surfactant synthesis at the level of a key regulatory enzyme by significantly altering the availability of inhibitory metabolites resulting from sphingomyelin hydrolysis.

Central carbon metabolism influences cellulase production in Bacillus licheniformis

2017 ◽  
Vol 66 (1) ◽  
pp. 49-54 ◽  
Author(s):  
J. Wang ◽  
S. Liu ◽  
Y. Li ◽  
H. Wang ◽  
S. Xiao ◽  
...  
Keyword(s):  
Bacillus Licheniformis ◽  
Carbon Metabolism ◽  
Cellulase Production ◽  
Central Carbon Metabolism ◽  
Central Carbon

Reinforcing potential of wood pulp-derived microfibres in a PVA matrix

Holzforschung ◽  
2006 ◽  
Vol 60 (1) ◽  
pp. 53-58 ◽  
Author(s):  
Ayan Chakraborty ◽  
Mohin Sain ◽  
Mark Kortschot
Keyword(s):  
Tensile Strength ◽  
Aspect Ratio ◽  
Polyvinyl Alcohol ◽  
Microcrystalline Cellulose ◽  
Comparative Studies ◽  
Kraft Pulp ◽  
Fold Increase ◽  
Minimum Length ◽  
Reinforcing Agent ◽  
Softwood Kraft Pulp

Abstract In this study, the reinforcing potential of cellulose “microfibres” obtained from bleached softwood kraft pulp was demonstrated in a matrix of polyvinyl alcohol (PVA). Microfibres are defined as fibres of cellulose of 0.1–1 μm in diameter, with a corresponding minimum length of 5–50 μm. Films cast with these microfibres in PVA showed a doubling of tensile strength and a 2.5-fold increase in stiffness with 5% microfibre loading. The theoretical stiffness of a microfibre was calculated as 69 GPa. The study also demonstrated that the strength of the composite was greater at 5% microfibre loading compared to 10% loading. Comparative studies with microcrystalline cellulose showed that the minimum aspect ratio of the reinforcing agent is more criticalthan its crystallinity in providing reinforcement in the composite.

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