scholarly journals Biosynthesis of amino acids in Clostridium pasteurianum

1970 ◽  
Vol 117 (3) ◽  
pp. 573-584 ◽  
Author(s):  
R. H. Dainty ◽  
J. L. Peel
Keyword(s):  
Amino Acids ◽  
Synthetic Medium ◽  
Carbon Sources ◽  
Cell Protein ◽  
Clostridium Pasteurianum ◽  
Metabolic Sequence ◽  
Series Of Experiments ◽  
Phosphoglycerate Dehydrogenase ◽  
The Individual

1. Clostridium pasteurianum was grown on a synthetic medium with the following carbon sources: (a) 14C-labelled glucose, alone or with unlabelled aspartate or glutamate, or (b) unlabelled glucose plus 14C-labelled aspartate, glutamate, threonine, serine or glycine. The incorporation of 14C into the amino acids of the cell protein was examined. 2. In both series of experiments carbon from exogenous glutamate was incorporated into proline and arginine; carbon from aspartate was incorporated into glutamate, proline, arginine, lysine, methionine, threonine, isoleucine, glycine and serine. Incorporations from the other exogenous amino acids indicated the metabolic sequence: aspartate → threonine → glycine ⇌ serine. 3. The following activities were demonstrated in cell-free extracts of the organism: (a) the formation of aspartate by carboxylation of phosphoenolpyruvate or pyruvate, followed by transamination; (b) the individual reactions of the tricarboxylic acid route to 2-oxoglutarate from oxaloacetate; glutamate dehydrogenase was not detected; (c) the conversion of aspartate into threonine via homoserine; (d) the conversion of threonine into glycine by a constitutive threonine aldolase; (e) serine transaminase, phosphoserine transaminase, glycerate dehydrogenase and phosphoglycerate dehydrogenase. This last activity was abnormally high. 4. The combined evidence indicates that in C. pasteurianum the biosynthetic role of aspartate and glutamate is generally similar to that in aerobic and facultatively aerobic organisms, but that glycine is synthesized from glucose via aspartate and threonine.

Regulation by amino acids of α-amylase and endo-β(1→4)-glucanase induction in mycelial culture of the mushroom Termitomyces clypeatus

1990 ◽  
Vol 36 (9) ◽  
pp. 617-624 ◽  
Author(s):  
Saswati Sengupta ◽  
S. Sengupta
Keyword(s):  
Amino Acids ◽  
Yeast Extract ◽  
Enzyme Production ◽  
Late Phase ◽  
Synthetic Medium ◽  
Extracellular Enzyme ◽  
Mycelial Culture ◽  
Termitomyces Clypeatus ◽  
Yeast Extract Medium

Termitomyces clypeatus constitutively liberated amyloglucosidase; the liberation was not repressed by glucose. Growth of the mushroom in synthetic medium was slow with starch, and only amyloglucosidase was liberated. Yeast extract stimulated growth and enzyme production in starch medium, and α-amylase along with amyloglucosidase was detected extracellularly. The mushroom could not utilise cellulose or liberate endo-β(1 → 4)-glucanase even when inducer cellobiose or glucose was added to cellulose at different concentrations. Cellobiose alone also failed to induce any extracellular endo-β(1 → 4)-glucanase production. Yeast extract in both cellulose and cellobiose media supported liberation of endo-β(1 → 4)-glucanase. Lactose was found to be a poor inducer even in yeast extract medium. However, both α-amylase and endo-β(1 → 4)-glucanase were detected intracellularly at a basal level even when the enzymes were absent extracellularly under inducing and noninducing conditions. The intracellular enzymes were only freely liberated into the medium in the presence of yeast extract. It appeared that induction of α-amylase and endo-β(1 → 4)-glucanase was largely inhibited by the restricted liberation of the enzymes in absence of yeast extract. Of the yeast extract components, amino acids were the active ingredient mimicking the role of yeast extract in induction. Yeast extract was found to relieve catabolic inhibition observed at the late phase of enzyme production. It is proposed that catabolic inhibition might have a role in the enzyme liberation and that amino acids supported extracellular enzyme production by relieving this inhibition. Key words: mushroom, Termitomyces clypeatus, catabolic inhibition, polysaccharidase induction, amino acid.

scholarly journals Effect of additional carbon source on biodegradation of linear alkylbenzene sulfonate by las-utilizing bacteria

2011 ◽  
Vol 1 (1) ◽  
pp. 2
Author(s):  
Kehinde I. Temitope Eniola
Keyword(s):  
Linear Alkylbenzene Sulfonate ◽  
Carbon Sources ◽  
Soluble Starch ◽  
Aerobic Biodegradation ◽  
Individual Species ◽  
Linear Alkylbenzene ◽  
Alkylbenzene Sulfonate ◽  
The Individual ◽  
Surfactant Biodegradation

Aerobic biodegradation of linear alkylbenzene sulfonate (LAS) by LAS-utilizing bacteria (LUB) in the presence of other sources of carbon (glucose and soluble starch) was examined. Biodegradation of LAS was monitored as primary degradation in terms of half-life (t½) of the surfactant. Biodegradation of LAS by the individual LUB was slower in the presence of Glucose. Biodegradation of the surfactant by the various consortia of LUB was slower in the presence of the carbon sources: t½ increased to 3 days. The rates of biodegradation by the consortia can be ranked as: four-membered (t½=9 days) > three-membered (t½=9 to 13 days) > two-membered consortia (t½=10 to 15 days). Generally, degradation in the presence of the carbon sources was faster with the consortia than the individual species. Degradation of the surfactant by the LUB was generally fastest in the absence of additional carbon sources. The possible role of additional carbon sources in persistence of surfactant in water bodies and the application of the observation in management of LAS-containing-effluent is suggested.

Plasma amino-acids in human cancer: the individual role of tumour, malnutrition and glucose tolerance

1988 ◽  
Vol 7 (4) ◽  
pp. 213-218 ◽  
Author(s):  
A. Cascino ◽  
C. Cangiano ◽  
F. Ceci ◽  
F. Franchi ◽  
E.T. Menichetti ◽  
...  
Keyword(s):  
Amino Acids ◽  
Glucose Tolerance ◽  
Human Cancer ◽  
Plasma Amino Acids ◽  
The Individual ◽  
Individual Role

ENERGY AND NITROGEN REQUIREMENTS OF MICROCOCCUS ROSEUS

1963 ◽  
Vol 9 (4) ◽  
pp. 633-642 ◽  
Author(s):  
R. C. Eisenberg ◽  
James B. Evans
Keyword(s):  
Amino Acids ◽  
Species Recognition ◽  
Synthetic Medium ◽  
Carbon Sources ◽  
Basal Medium ◽  
Sole Source ◽  
Carbon And Nitrogen ◽  
Excellent Growth ◽  
Micrococcus Roseus ◽  
Do So

A collection of pink-pigmented micrococci has been studied and found to be a relatively homogeneous group that deserve species recognition as Micrococcus roseus. These organisms are salt-tolerant obligate aerobes that usually reduce nitrates and do not hydrolyze gelatin. They can utilize xylose, glucose, fructose, mannose, galactose, sucrose, acetate, pyruvate, lactate, malate, succinate, and gluconate as carbon and energy sources. Most strains also can utilize arabinose, lactose, maltose, glycerol, mannitol, sorbitol, and propionate. A synthetic basal medium has been devised that will give excellent growth of these organisms with glutamic acid as the sole source of nitrogen, carbon, and energy. Two vitamins, biotin and thiamine, are required by all strains, and are the only vitamins in the synthetic medium that was used to study interrelationships between nitrogen and carbon sources. Ammonia can serve as the sole source of nitrogen when glucose, or certain other substrates, is the sole source of carbon and energy. Not all substrates that can supply energy in a complex medium can do so in the synthetic medium with ammonia as the sole source of nitrogen. Some amino acids in addition to glutamate have a limited ability to serve as a source of both carbon and nitrogen. The ability of individual amino acids to serve as a sole source of nitrogen depends upon the nature of the substrate that is present as a carbon and energy source.

Regulation of proteolytic enzyme production by Aeromonas proteolytica. I. Extracellular endopeptidase

1970 ◽  
Vol 16 (1) ◽  
pp. 17-22 ◽  
Author(s):  
Carol D. Litchfield ◽  
J. M. Prescott
Keyword(s):  
Amino Acids ◽  
Catabolite Repression ◽  
Enzyme Production ◽  
Proteolytic Enzyme ◽  
Inverse Relationship ◽  
Carbon Sources ◽  
Complex Mixtures ◽  
Growth Media ◽  
Nutritional Factors ◽  
The Individual

The production of extracellular endopeptidase by Aeromonas proteolytica Merkel et al. was found to be influenced by a number of nutritional factors. An inverse relationship existed between endopeptidase synthesis and growth in media containing increasing quantities of asparagine. This effect was accentuated by the individual addition of glycerol, glucose, sucrose, or acetate as supplemental carbon sources. The addition of small quantities of complex mixtures of peptides to growth media containing either acid-hydrolyzed casein or asparagine as the organic component greatly stimulated endopeptidase synthesis. The data suggest that endopeptidase synthesis is repressed when A. proteolytica is grown in the presence of certain individual amino acids, that glycerol and some other easily metabolized compounds cause catabolite repression of endopeptidase synthesis, and that endopeptidase production is stimulated by peptides of unknown identity.

REGULATION OF PROTEINASE FORMATION IN A SPECIES OF MICROCOCCUS

1966 ◽  
Vol 12 (6) ◽  
pp. 1175-1185 ◽  
Author(s):  
I. J. McDonald ◽  
Alice K. Chambers
Keyword(s):  
Amino Acids ◽  
Protein Synthesis ◽  
Carbon Source ◽  
Glutamic Acid ◽  
Aspartic Acid ◽  
Synthetic Medium ◽  
Carbon Sources ◽  
Extracellular Proteinase ◽  
Proteinase Production

Micrococcus sp. ATCC No. 407 (M. freudenreichii) produced relatively large amounts of extracellular proteinase in synthetic medium containing methionine, thiamine, biotin, NH4Cl, NaHCO3, NaCl, MgSO4, and FeSO4, with aspartic acid, asparagine, glutamic acid, or glutamine as the carbon source. The organism produced relatively small amounts of proteinase with succinate, malate, fumarate, maltose, maltotriose, or maltotetraose as the carbon source. In synthetic medium containing maltose, any one of several amino acids stimulated growth and proteinase production. The results indicated that the organism is a partial constitutive strain with respect to proteinase production and suggested that proteinase formation is controlled by a form of end-product induction. In the presence of inducer, carbon sources such as succinate or maltose caused suppression of proteinase formation, suggesting control by metabolic repression as well. Because extracellular proteinase formation is induced by amino acids and suppressed by carbon sources such as succinate or maltose, and because the organism can utilize amino acids as carbon sources for growth, it. is suggested that the function of extracellular proteinase in this organism is to ensure a supply of carbon for growth rather than a supply of amino acids for protein synthesis.

School Success and School Engagement of Immigrant Children and Adolescents

2013 ◽  
Vol 18 (2) ◽  
pp. 126-135 ◽  
Author(s):  
Frosso Motti-Stefanidi ◽  
Ann S. Masten
Keyword(s):  
Academic Achievement ◽  
Academic Success ◽  
Children And Adolescents ◽  
School Engagement ◽  
School Success ◽  
Immigrant Children ◽  
Integrative Model ◽  
High Stakes ◽  
The Individual

Academic achievement in immigrant children and adolescents is an indicator of current and future adaptive success. Since the future of immigrant youths is inextricably linked to that of the receiving society, the success of their trajectory through school becomes a high stakes issue both for the individual and society. The present article focuses on school success in immigrant children and adolescents, and the role of school engagement in accounting for individual and group differences in academic achievement from the perspective of a multilevel integrative model of immigrant youths’ adaptation ( Motti-Stefanidi, Berry, Chryssochoou, Sam, & Phinney, 2012 ). Drawing on this conceptual framework, school success is examined in developmental and acculturative context, taking into account multiple levels of analysis. Findings suggest that for both immigrant and nonimmigrant youths the relationship between school engagement and school success is bidirectional, each influencing over time the other. Evidence regarding potential moderating and mediating roles of school engagement for the academic success of immigrant youths also is evaluated.

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