scholarly journals Improved Laccase Production by Trametes pubescens MB89 in Distillery Wastewaters

2011 ◽  
Vol 2011 ◽  
pp. 1-8 ◽  
Author(s):  
P. J. Strong
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Culture Medium ◽  
Glucose Repression ◽  
Laccase Production ◽  
Copper Addition ◽  
Single Addition ◽  
Complex Nitrogen Source ◽  
Multiple Factor ◽  
Synergistic Increase

Various culture parameters were optimised for laccase synthesis by Trametes pubescens MB89, including pH, carbon source, nitrogen source, lignocellulosic supplements, and reported inducers. Glucose, in conjunction with a complex nitrogen source at pH 5.0, resulted in the highest laccase yield. Adding ethanol, copper, or 2,5-xylidine prior to inoculation further improved laccase concentrations. The addition of 2,5-xylidine was further investigated with multiple additions applied at varying times. This novel application substantially improved laccase production when applied regularly from inoculation and during the growth phase, and also countered glucose repression of laccase synthesis. Single and multiple factor changes were studied in three distillery wastewaters and a wine lees. A synergistic increase in laccase synthesis was observed with the addition of glucose, copper, and 2,5-xylidine. Single addition of 2,5-xylidine proved most beneficial with distillery wastewaters, while copper addition was most beneficial when using the wine lees as a culture medium.

scholarly journals Ligninase Profiling and Optimization of Laccase Production from Indigenous Wood Rot Fungus (WRF) KLUM2 in Kirk Medium-Alkali Lignin Kayu Jati (MK-ALKJ)

2021 ◽  
Vol 7 (1) ◽  
pp. 75-82
Author(s):  
Siti Mutmainah ◽  
Evi Susanti
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Specific Activity ◽  
Laccase Production ◽  
Temperature Variations ◽  
Alkali Lignin ◽  
Experimental Laboratory ◽  
Teak Wood ◽  
The One ◽  
Suspension Preparation

The production of ligninase by wood rot fungus (WRF) is determined by carbon source and growth condition. The goal of this study is to determine the ligninase profile produced by WRF KLUM2 in Kirk Medium using teak wood alkaline lignin as a carbon source known as Kirk Medium-Alkali lignin Kayu Jati (MK-ALKJ), optimization of dominant ligninase production in the MK-ALKJ compared to the one that is produced in the Kirk’s medium with glucose as a carbon source (MK-Glucose). This research was conducted in an experimental laboratory consisting of: (1) spore suspension preparation, (2) ligninase profiling at various growth times, (3) ligninase profiling at various temperature variations, (4) optimization of laccase production including pH and the amount of nitrogen source. Growth was identified based on the specific activity of lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase. The results showed that relatively the three types of ligninase, namely LiP, MnP, and laccase, were produced in the same amount by the wood rotting fungus isolates KLUM2 in MK-ALJK. All three were produced with the highest yield of respectively 55.65; 52.48; 57.64 U/mg. Laccase as the dominant ligninase can be optimized to reach 83.52 U/mg by inoculating 2.107 spore cells in MK-ALKJ in 37 °C, pH = 3.5, and a nitrogen source of 20mM (NH4)2SO4 for 6 days. Therefore, it can be concluded that the ligninase activity of indigenous WRF KLUM2 in MK-ALJK medium is higher than in the MK-Glucose.

Research on microbial lipid production from potato starch wastewater as culture medium by Lipomyces starkeyi

2013 ◽  
Vol 67 (8) ◽  
pp. 1802-1808 ◽  
Author(s):  
Jun-Xian Liu ◽  
Qin-Yan Yue ◽  
Bao-Yu Gao ◽  
Yan Wang ◽  
Qian Li ◽  
...  
Keyword(s):  
Cell Growth ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Culture Medium ◽  
Potato Starch ◽  
Inoculum Size ◽  
Microbial Lipid ◽  
Lipomyces Starkeyi ◽  
Starch Wastewater ◽  
Source Concentration

In this paper, potato starch wastewater as culture medium was treated by the oleaginous yeast Lipomyces starkeyi to biosynthesize microbial lipid. The result indicated that carbon source types, carbon source concentration, nitrogen source types, nitrogen source concentration, inoculum size, and cultivation time all had a significant effect on cell growth and microbial lipid accumulation in batch cultures. A measure of 120 g/L of glucose concentration, 3.0 g/L of (NH4)2SO4 concentration, 10% inoculum size, and incubation time 96 h cultivated in a shaking flask at 30 °C were found to be the optimal conditions not only for cell growth but also for lipid synthesis. Under this condition, the cellular biomass and lipid content could reach 2.59 g/L and 8.88%, respectively. This work provides a new method for effective utilization of potato starch wastewater, which has particular social and economic benefits for yeast treatment technology.

scholarly journals Phytotoxin produced by Bipolaris euphorbiae in-vitro is effective against the weed Euphorbia heterophylla

2002 ◽  
Vol 45 (2) ◽  
pp. 233-240 ◽  
Author(s):  
Aneli M. Barbosa ◽  
Cristina G. M. Souza ◽  
Robert F. H. Dekker ◽  
Rafael C. Fonseca ◽  
Dalva T. Ferreira
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Carbon Source ◽  
Host Plants ◽  
Culture Medium ◽  
Virulent Strain ◽  
Fungal Strain ◽  
Malt Extract ◽  
Mato Grosso

Four virulent strain isolates of the fungus, Bipolaris euphorbiae (previously identified as a Helminthosporium sp.), isolated from host plants in four states within Brazil were screened for the production of phytotoxins that promoted wilting and defoliation of the Brazilian weed, Euphorbia heterophylla, commonly found growing among soyabean crops. Only one isolate, B. euphorbiae Strain I (EUPH petropar from Mato Grosso state), produced phytotoxin in-vitro when grown in stationary culture for 7 d at 28 ° C on minimum salts medium supplemented with 1.5 % glucose as the sole carbon source. Phytotoxin was also produced when the fungal strain was grown on fructose, galactose, mannose, xylose and sucrose. The addition of nitrogen source (yeast extract, peptone or malt extract) to the culture medium did not influence phytotoxin production. The phytotoxin produced by Strain I was most active at pH 6.0, stable between pH 3-9, and was highly thermostable, remaining fully active when heated at 90 ° C for 1 h.

Studies on the Biological Characteristics of Termitomyces Albuminosus Hypha

2013 ◽  
Vol 709 ◽  
pp. 810-813 ◽  
Author(s):  
Xiong Ya ◽  
Min Jie Li
Keyword(s):  
Growth Factors ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Biological Characteristics ◽  
Edible Fungi ◽  
Growth Environment ◽  
Wild Edible Fungi ◽  
Development And Utilization

Termitomyces albuminosus is a kind of local distinctive wild edible fungi in southwest of China. It is delicious, rich in nutrition and has high development and utilization value, but owing to the restrictions of growth environment, it can not be cultivated artificially. This article mainly studied on the biological characteristics of Termitomyces albuminosus Hypha, and found out the optimal carbon source, nitrogen source, growth factors and the C/N ratio that are suitable for the growth of Hypha of Termitomyces albuminosus .

scholarly journals Monomethylamine as a Nitrogen Source for a Nonmethylotrophic Bacterium, Agrobacterium tumefaciens

2010 ◽  
Vol 76 (12) ◽  
pp. 4102-4104 ◽  
Author(s):  
Yin Chen ◽  
Kathryn L. McAleer ◽  
J. Colin Murrell
Keyword(s):  
Agrobacterium Tumefaciens ◽  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Nitrogen Source ◽  
Key Enzymes ◽  
Genes Encoding

ABSTRACT Monomethylamine can be used by nonmethylotrophs as a sole nitrogen source but not as a carbon source; however, little is known about the genes and enzymes involved. The γ-glutamylmethylamide/N-methylglutamate pathway for monomethylamine utilization by methylotrophs has recently been resolved. We have identified genes encoding key enzymes of this pathway in nonmethylotrophs (e.g., Agrobacterium tumefaciens) and demonstrated that this pathway is also involved in the utilization of monomethylamine as a nitrogen source by nonmethylotrophs.

scholarly journals Mutants affecting histidine utilization inAspergillus nidulans

1975 ◽  
Vol 25 (2) ◽  
pp. 119-135 ◽  
Author(s):  
Meryl Polkinghorne ◽  
M. J. Hynes
Keyword(s):  
Carbon Source ◽  
Nitrogen Source ◽  
Sole Carbon Source ◽  
Nitrogen Sources ◽  
Limiting Factor ◽  
Sole Nitrogen Source ◽  
Wild Type ◽  
Exogenous Substrate ◽  
Growth Properties ◽  
Type Strains

SUMMARYWild-type strains ofAspergillus nidulansgrow poorly onL-histidine as a sole nitrogen source. The synthesis of the enzyme histidase (EC. 4.3.1.3) appears to be a limiting factor in the growth of the wild type, as strains carrying the mutantareA102 allele have elevated histidase levels and grow strongly on histidine as a sole nitrogen source.L-Histidine is an extremely weak sole carbon source for all strains.Ammonium repression has an important role in the regulation of histidase synthesis and the relief of ammonium repression is dependent on the availability of a good carbon source. The level of histidase synthesis does not respond to the addition of exogenous substrate.Mutants carrying lesions in thesarA orsarB loci (suppressor ofareA102) have been isolated. The growth properties of these mutants on histidine as a sole nitrogen source correlate with the levels of histidase synthesized. Mutation at thesarA andsarB loci also reduces the utilization of a number of other nitrogen sources. The data suggest that these two genes may code for regulatory products involved in nitrogen catabolism. No histidase structural gene mutants were identified and possible explanations of this are discussed.

Regulation of yeast COX6 by the general transcription factor ABF1 and separate HAP2- and heme-responsive elements

1992 ◽  
Vol 12 (5) ◽  
pp. 2302-2314
Author(s):  
J D Trawick ◽  
N Kraut ◽  
F R Simon ◽  
R O Poyton
Keyword(s):  
Transcription Factor ◽  
Carbon Source ◽  
Protein Binding ◽  
Glucose Repression ◽  
Protein Complexes ◽  
Carbon Sources ◽  
Major Protein ◽  
Mobility Shift ◽  
Gel Mobility Shift ◽  
In Cells

Transcription of the Saccharomyces cerevisiae COX6 gene is regulated by heme and carbon source. It is also affected by the HAP2/3/4 transcription factor complex and by SNF1 and SSN6. Previously, we have shown that most of this regulation is mediated through UAS6, an 84-bp upstream activation segment of the COX6 promoter. In this study, by using linker scanning mutagenesis and protein binding assays, we have identified three elements within UAS6 and one element downstream of it that are important. Two of these, HDS1 (heme-dependent site 1; between -269 and -251 bp) and HDS2 (between -228 and -220 bp), mediate regulation of COX6 by heme. Both act negatively. The other two elements, domain 2 (between -279 and -269 bp) and domain 1 (between -302 and -281 bp), act positively. Domain 2 is required for optimal transcription in cells grown in repressing but not derepressing carbon sources. Domain 1 is essential for transcription per se in cells grown on repressing carbon sources, is required for optimal transcription in cells grown on a derepressing carbon source, is sufficient for glucose repression-derepression, and is the element of UAS6 at which HAP2 affects COX6 transcription. This element contains the major protein binding sites within UAS6. It has consensus binding sequences for ABF1 and HAP2. Gel mobility shift experiments show that domain 1 binds ABF1 and forms different numbers of DNA-protein complexes in extracts from cells grown in repressing or derepressing carbon sources. In contrast, gel mobility shift experiments have failed to reveal that HAP2 or HAP3 binds to domain 1 or that hap3 mutations affect the complexes bound to it. Together, these findings permit the following conclusions: COX6 transcription is regulated both positively and negatively; heme and carbon source exert their effects through different sites; domain 1 is absolutely essential for transcription on repressing carbon sources; ABF1 is a major component in the regulation of COX6 transcription; and the HAP2/3/4 complex most likely affects COX6 transcription indirectly.

Expression of the transcriptional activator LAC9 (KlGAL4) in Kluyveromyces lactis is controlled by autoregulation

1993 ◽  
Vol 13 (5) ◽  
pp. 3058-3066
Author(s):  
W Zachariae ◽  
K D Breunig
Keyword(s):  
Carbon Source ◽  
Binding Site ◽  
Glucose Repression ◽  
Kluyveromyces Lactis ◽  
Transcriptional Activator ◽  
Optimal Growth ◽  
Source Control ◽  
Poor Growth ◽  
Protein Protein Interaction ◽  
Metabolic Genes

The concentration of the transcriptional activator LAC9 (KlGAL4) of Kluyveromyces lactis is moderately regulated by the carbon source as is the case for GAL4, its homolog in Saccharomyces cerevisiae. Expression of the LAC9 gene is induced about twofold in galactose. This induction is due to autoregulation. The LAC9 gene product binds to a low-affinity binding site in the LAC9 promoter and moderately activates transcription in response to galactose above a basal level. As for the LAC9-controlled metabolic genes, induction of LAC9 is inhibited in the presence of glucose. This inhibition of induction is a prerequisite for glucose repression of the lactose-galactose metabolic pathway. On the other hand, induced LAC9 levels are required for optimal growth on galactose, since mutating the LAC9 binding site in the LAC9 promoter resulted in poor growth and reduced expression of LAC9-controlled genes. Thus, in addition to the GAL80-dependent regulation by protein-protein interaction, the regulation of LAC9 gene expression is an important parameter in determining carbon source control of the LAC-GAL regulon. Although the mode of control is different, the pattern of LAC9 gene regulation resembles that of the S. cerevisiae GAL4 gene, being lower in glucose and glucose-galactose than in galactose.

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