The Effect of Several Protein Amino Acids and Some Inorganic Nitrogen Sources on the Growth of Sphagnum nemoreum

1975 ◽  
Vol 35 (3) ◽  
pp. 194-199 ◽  
Author(s):  
LIISA KAARINA SIMOLA
Keyword(s):  
Amino Acids ◽  
Inorganic Nitrogen ◽  
Nitrogen Sources ◽  
Protein Amino Acids

Nitrogen nutrition and regulation of cephalosporin production in Streptomyces clavuligerus

1979 ◽  
Vol 25 (1) ◽  
pp. 61-67 ◽  
Author(s):  
Yair Aharonowitz ◽  
Arnold L. Demain
Keyword(s):  
Amino Acids ◽  
Growth Rate ◽  
Nitrogen Nutrition ◽  
Antibiotic Production ◽  
Inorganic Nitrogen ◽  
Amino Nitrogen ◽  
Nitrogen Sources ◽  
Streptomyces Clavuligerus ◽  
Defined Medium ◽  
Repressive Effect

When used as sole nitrogen source, certain amino acids (e.g., proline, asparagine) supported both growth and sporulation by Streptomyces clavuligerus streaked onto solid defined medium. Ammonium supported growth but suppressed sporulation. Amino nitrogen was best for cephalosporin production in liquid defined medium, although urea was almost as useful. A comparison of amino acids showed asparagine and glutamine to be the best nitrogen sources and arginine to be almost as good. Ammonium salts supported a somewhat lower growth rate than asparagine, but antibiotic production was very poor on these inorganic nitrogen sources. Addition of ammonium to asparagine did not affect growth rate but increased mycelial mass; cephalosporin production was reduced by about 75%. Antibiotic production was more closely associated with growth in the absence of ammonium than in its presence, indicating a strong inhibitory and (or) repressive effect of NH4+ on antibiotic production. Ammonium exerted its negative effect when added at 24 h or earlier, i.e. before antibiotic formation began.

scholarly journals Nitrate Promotes Capsaicin Accumulation inCapsicum chinenseImmobilized Placentas

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Jeanny G. Aldana-Iuit ◽  
Enrique Sauri-Duch ◽  
María de Lourdes Miranda-Ham ◽  
Lizbeth A. Castro-Concha ◽  
Luis F. Cuevas-Glory ◽  
...  
Keyword(s):  
Amino Acids ◽  
Structural Damage ◽  
Inorganic Nitrogen ◽  
Placental Tissue ◽  
Nitrogen Sources ◽  
Nitrate Content ◽  
Tissue Sections ◽  
Scanning Electron Microcopy ◽  
Branched Amino Acids

In chili pepper’s pods, placental tissue is responsible for the synthesis of capsaicinoids (CAPs), the compounds behind their typical hot flavor or pungency, which are synthesized from phenylalanine and branched amino acids. Placental tissue sections from Habanero peppers (Capsicum chinenseJacq.) were immobilized in a calcium alginate matrix and culturedin vitro, either continuously for 28 days or during two 14-day subculture periods. Immobilized placental tissue remained viable and metabolically active for up to 21 days, indicating its ability to interact with media components. CAPs contents abruptly decreased during the first 7 days in culture, probably due to structural damage to the placenta as revealed by scanning electron microcopy. CAPs levels remained low throughout the entire culture period, even though a slight recovery was noted in subcultured placentas. However, doubling the medium’s nitrate content (from 40 to 80 mM) resulted in an important increment, reaching values similar to those of intact pod’s placentas. These data suggest that isolated pepper placentas culturedin vitroremain metabolically active and are capable of metabolizing inorganic nitrogen sources, first into amino acids and, then, channeling them to CAP synthesis.

Interactions between nitrogen sources and xylose affecting growth, sporulation, and polyphenoloxidase activity in Bipolaris maydis race T

1981 ◽  
Vol 59 (11) ◽  
pp. 2102-2107 ◽  
Author(s):  
Robert C. Evans ◽  
Candace L. Black
Keyword(s):  
Amino Acids ◽  
Organic Nitrogen ◽  
Inorganic Nitrogen ◽  
Nitrogen Concentration ◽  
Relative Effectiveness ◽  
Nitrogen Sources ◽  
Dry Weight ◽  
The Other ◽  
Growth Media ◽  
Bipolaris Maydis

The effect of 23 organic and 3 inorganic nitrogen sources on growth, sporulation, and polyphenoloxidase activity was measured in Bipolaris maydis race T incubated with or without a xylose supplement. Mycelial dry weight tends to be highest on acidic and other polar amino acids and least on nonpolar ones; organic nitrogen sources generally result in greater dry weight than inorganic ones. Changes in nitrogen concentration and pH of media influence growth and sporulation, but only pH alters the relative effectiveness of the nitrogen sources on these processes. The addition of xylose to the growth media has little effect on growth. However, in the presence of lysine, serine, asparagine, glycine, γ-alanine, alanine, and α-aminobutyrate, xylose causes an increase in sporulation and a concomitant decrease in polyphenoloxidase activity. There is no consistent pattern resulting from xylose addition in the presence of the other nitrogen sources.

scholarly journals Nectar non-protein amino acids (NPAAs) do not change nectar palatability but enhance learning and memory in honey bees

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Daniele Carlesso ◽  
Stefania Smargiassi ◽  
Elisa Pasquini ◽  
Giacomo Bertelli ◽  
David Baracchi
Keyword(s):  
Amino Acids ◽  
Learning And Memory ◽  
Honey Bees ◽  
Feeding Preference ◽  
Memory Retention ◽  
Floral Nectar ◽  
Olfactory Conditioning ◽  
Specific Memory ◽  
Protein Amino Acids ◽  
Valuable Compounds

AbstractFloral nectar is a pivotal element of the intimate relationship between plants and pollinators. Nectars are composed of a plethora of nutritionally valuable compounds but also hundreds of secondary metabolites (SMs) whose function remains elusive. Here we performed a set of behavioural experiments to study whether five ubiquitous nectar non-protein amino acids (NPAAs: β-alanine, GABA, citrulline, ornithine and taurine) interact with gustation, feeding preference, and learning and memory in Apis mellifera. We showed that foragers were unable to discriminate NPAAs from water when only accessing antennal chemo-tactile information and that freely moving bees did not exhibit innate feeding preferences for NPAAs. Also, NPAAs did not alter food consumption or longevity in caged bees over 10 days. Taken together our data suggest that natural concentrations of NPAAs did not alter nectar palatability to bees. Olfactory conditioning assays showed that honey bees were more likely to learn a scent when it signalled a sucrose reward containing either β-alanine or GABA, and that GABA enhanced specific memory retention. Conversely, when ingested two hours prior to conditioning, GABA, β-alanine, and taurine weakened bees’ acquisition performances but not specific memory retention, which was enhanced in the case of β-alanine and taurine. Neither citrulline nor ornithine affected learning and memory. NPAAs in nectars may represent a cooperative strategy adopted by plants to attract beneficial pollinators.

Protection of Italian ryegrass (Lolium multiflorum L.) seedlings from salinity stress following seed priming with L-methionine and casein hydrolysate

2020 ◽  
pp. 1-9
Author(s):  
Keum-Ah Lee ◽  
Youngnam Kim ◽  
Hossein Alizadeh ◽  
David W.M. Leung
Keyword(s):  
Oxidative Stress ◽  
Amino Acids ◽  
Salinity Stress ◽  
Lolium Multiflorum ◽  
Casein Hydrolysate ◽  
Seed Priming ◽  
Germination Percentage ◽  
Italian Ryegrass ◽  
Significant Difference ◽  
Protein Amino Acids

Abstract Seed priming with water (hydropriming or HP) has been shown to be beneficial for seed germination and plant growth. However, there is little information on the effects of seed priming with amino acids and casein hydrolysate (CH) compared with HP, particularly in relation to early post-germinative seedling growth under salinity stress. In this study, Italian ryegrass seeds (Lolium multiflorum L.) were primed with 1 mM of each of the 20 protein amino acids and CH (200 mg l−1) before they were germinated in 0, 60 and 90 mM NaCl in Petri dishes for 4 d in darkness. Germination percentage (GP), radicle length (RL) and peroxidase (POD) activity in the root of 4-d-old Italian ryegrass seedlings were investigated. Generally, when the seeds were germinated in 0, 60 and 90 mM NaCl, there was no significant difference in GP of seeds among various priming treatments, except that a higher GP was observed in seeds of HP treatment compared with the non-primed seeds when incubated in 60 mM NaCl. When incubated in 60 and 90 mM NaCl, seedlings from seeds primed with L-methionine or CH exhibited greater RL (greater protection against salinity stress) and higher root POD activity than those from non-primed and hydro-primed seeds. Under salinity stress, there were higher levels of malondialdehyde (MDA) in the root of 4-d-old Italian ryegrass seedlings, a marker of oxidative stress, but seed priming with CH was effective in reducing the salinity-triggered increase in MDA content. These results suggest that priming with L-methionine or CH would be better than HP for the protection of seedling root growth under salinity stress and might be associated with enhanced antioxidative defence against salinity-induced oxidative stress.

scholarly journals The key amino acids of E protein involved in early flavivirus infection: viral entry

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
Tao Hu ◽  
Zhen Wu ◽  
Shaoxiong Wu ◽  
Shun Chen ◽  
Anchun Cheng
Keyword(s):  
Amino Acids ◽  
Conformational Changes ◽  
Viral Entry ◽  
Envelope Protein ◽  
Cell Attachment ◽  
Envelope Proteins ◽  
Infection Process ◽  
Early Infection ◽  
Protein Amino Acids ◽  
Α Helix

AbstractFlaviviruses are enveloped viruses that infect multiple hosts. Envelope proteins are the outermost proteins in the structure of flaviviruses and mediate viral infection. Studies indicate that flaviviruses mainly use envelope proteins to bind to cell attachment receptors and endocytic receptors for the entry step. Here, we present current findings regarding key envelope protein amino acids that participate in the flavivirus early infection process. Among these sites, most are located in special positions of the protein structure, such as the α-helix in the stem region and the hinge region between domains I and II, motifs that potentially affect the interaction between different domains. Some of these sites are located in positions involved in conformational changes in envelope proteins. In summary, we summarize and discuss the key envelope protein residues that affect the entry process of flaviviruses, including the process of their discovery and the mechanisms that affect early infection.

Ileal digestibility of protein and amino acids of feed peas with different trypsin inhibitor activity in pigs

2000 ◽  
Vol 80 (4) ◽  
pp. 643-652 ◽  
Author(s):  
F. Grosjean ◽  
C. Jondreville ◽  
I. Williatte-Hazouard ◽  
F. Skiba ◽  
B. Carrouée ◽  
...  
Keyword(s):  
Amino Acids ◽  
Trypsin Inhibitor ◽  
Crude Protein ◽  
Trypsin Inhibitor Activity ◽  
Rectal Anastomosis ◽  
Inhibitor Activity ◽  
Ileal Digestibility ◽  
Physical Chemical ◽  
Protein Amino Acids ◽  
Weight Proportion

Ileal digestibility of protein and amino acids was measured in pigs fed 13 round, tannin-free peas samples and related to the following physical, chemical and biological characteristics of these samples: thousand-seed weight, proportion of hulls, starch, fibre, crude protein, ether extract and ash contents, trypsin inhibitor activity and trypsin inhibitor activity per unit of crude protein (TIAP). Each pea sample was included in a diet containing starch, sucrose, minerals and vitamins and fed to four barrows (50 to 100 kg) fitted with an end-to-end ileo-rectal anastomosis. Standardised ileal protein and amino acid digestibilities, except for alanine of peas decreased linearly with increasing TIAP (P < 0.01) and was not affected by fiber content. For example standardized ileal digestibilities values (%) decreased by −0.1975, −0.1617, −0.2171, −0.2630, −0.2029 and −0.3536 per unit of TIAP (expressed in unit of trypsin inhibited per milligram crude protein), respectively, for crude protein and lysine, threonine, methionine, cystine and tryptophan. Key words: Peas, trypsin inhibitor activity, standardised ileal digestibilities, protein, amino acids, pig

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