Autophagy regulates whitefly–symbiont metabolic interactions

2021 ◽  
Author(s):  
Yan-Bin Wang ◽  
Ce Li ◽  
Jin-Yang Yan ◽  
Tian-Yu Wang ◽  
Ya-Lin Yao ◽  
...  
Keyword(s):  
Amino Acid ◽  
Essential Amino Acid ◽  
Critical Role ◽  
Dietary Supplementation ◽  
B Vitamins ◽  
Host Cells ◽  
Cellular Mechanisms ◽  
Essential Nutrients ◽  
Metabolic Interactions ◽  
B Vitamin

Nutritional symbionts are restricted to specialized host cells called bacteriocytes in various insect orders. These symbionts can provide essential nutrients to the host. However, the cellular mechanisms underlying the regulation of these insect–symbiont metabolic associations remain largely unclear. The whitefly, Bemisia tabaci MEAM1, hosts Portiera and Hamiltonella bacteria in the same bacteriocyte. In this study, the induction of autophagy by chemical treatment and gene silencing decreased symbiont titers, and essential amino acid (EAA) and B vitamin contents. In contrast, the repression of autophagy in bacteriocytes via Atg8 silencing increased symbiont titers, and amino acid and B vitamin contents. Furthermore, dietary supplementation with non-EAAs or B vitamins alleviated autophagy in whitefly bacteriocytes, elevated TOR (target of rapamycin) expression and increased symbiont titers. TOR silencing restored symbiont titers in whiteflies after dietary supplementation with B vitamins. These data suggest that Portiera and Hamiltonella evade autophagy of the whitefly bacteriocytes by activating the TOR pathway via providing essential nutrients. Taken together, we demonstrated that autophagy plays a critical role in regulating the metabolic interactions between the whitefly and two intracellular symbionts. Therefore, this study reveals that autophagy is an important cellular basis for bacteriocyte evolution and symbiosis persistence in whiteflies. The whitefly symbiosis unravels the interactions between cellular and metabolic functions of bacteriocytes. Importance Nutritional symbionts, which are restricted to specialized host cells called bacteriocytes, can provide essential nutrients for many hosts. However, the cellular mechanisms of regulation of animal–symbiont metabolic associations have been largely unexplored. Here, using the whitefly- Portiera / Hamiltonella endosymbiosis, we demonstrate autophagy regulates the symbiont titers, and thereby alters the essential amino acid and B vitamin contents. For persistence in the whitefly bacteriocytes, Portiera and Hamiltonella alleviate autophagy by activating the TOR (target of rapamycin) pathway through providing essential nutrients. Therefore, we demonstrate that autophagy plays a critical role in regulating the metabolic interactions between the whitefly and two intracellular symbionts. This study also provides insight into the cellular basis of bacteriocyte evolution and symbiosis persistence in the whitefly. The mechanisms underlying the role of autophagy in whitefly symbiosis could be widespread in many insect nutritional symbioses. These findings provide new avenue for whitefly control via regulating autophagy in the future.

scholarly journals Signatures of host/symbiont genome coevolution in insect nutritional endosymbioses

2015 ◽  
Vol 112 (33) ◽  
pp. 10255-10261 ◽  
Author(s):  
Alex C. C. Wilson ◽  
Rebecca P. Duncan
Keyword(s):  
Amino Acid ◽  
Genome Evolution ◽  
Genetic Material ◽  
Cell Lineage ◽  
Host Cells ◽  
Cellular Mechanisms ◽  
New Era ◽  
Branched Chain ◽  
Symbiosis Research ◽  
Symbiont Genome

The role of symbiosis in bacterial symbiont genome evolution is well understood, yet the ways that symbiosis shapes host genomes or more particularly, host/symbiont genome coevolution in the holobiont is only now being revealed. Here, we identify three coevolutionary signatures that characterize holobiont genomes. The first signature, host/symbiont collaboration, arises when completion of essential pathways requires host/endosymbiont genome complementarity. Metabolic collaboration has evolved numerous times in the pathways of amino acid and vitamin biosynthesis. Here, we highlight collaboration in branched-chain amino acid and pantothenate (vitamin B5) biosynthesis. The second coevolutionary signature is acquisition, referring to the observation that holobiont genomes acquire novel genetic material through various means, including gene duplication, lateral gene transfer from bacteria that are not their current obligate symbionts, and full or partial endosymbiont replacement. The third signature, constraint, introduces the idea that holobiont genome evolution is constrained by the processes governing symbiont genome evolution. In addition, we propose that collaboration is constrained by the expression profile of the cell lineage from which endosymbiont-containing host cells, called bacteriocytes, are derived. In particular, we propose that such differences in bacteriocyte cell lineage may explain differences in patterns of host/endosymbiont metabolic collaboration between the sap-feeding suborders Sternorrhyncha and Auchenorrhynca. Finally, we review recent studies at the frontier of symbiosis research that are applying functional genomic approaches to characterization of the developmental and cellular mechanisms of host/endosymbiont integration, work that heralds a new era in symbiosis research.

scholarly journals Human hepatic tryptophan 2,3-dioxygenase ubiquitin-dependent protein degradation: The critical role of its exosite as the molecular lynchpin of its substrate-mediated protein stabilization

2019 ◽  
Author(s):  
Sung-Mi Kim ◽  
Yi Liu ◽  
YongQiang Wang ◽  
Shay Karkashon ◽  
Ariel Lewis-Ballester ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Amino Acid ◽  
Essential Amino Acid ◽  
Opposite Effect ◽  
Critical Role ◽  
Protein Stabilization ◽  
High Affinity ◽  
Dependent Protein ◽  
Rate Limiting

AbstractHepatic tryptophan 2,3-dioxygenase (TDO) is a cytoplasmic homotetrameric hemoprotein and the rate-limiting enzyme in the irreversible degradation of the essential amino acid L-tryptophan (L-Trp) to N-formylkynurenine, thus controlling the flux of L-Trp into its serotonergic and kynureninic/NAD pathways. TDO has long been recognized to be substrate-inducible via protein stabilization, but the molecular mechanism of this stabilization has remained elusive. Recent elucidation of human TDO (hTDO) crystal structure has identified a high-affinity (Kd ≈ 0.5 μM) Trp-binding exosite in each of its 4 monomeric subunits. Mutation of the Glu105, Trp208 and Arg211 comprising this exosite not only abolished the high-affinity L-Trp binding, but also accelerated the ubiquitin-dependent proteasomal degradation of hTDO. We have further characterized this hTDO degradation by documenting that its ubiquitination by gp78/AMFR and CHIP E2/E3 ligase complexes occurs on external Lys-residues within or vicinal to acidic Asp/Glu and phosphorylated pSer/pThr (DEpSpT)-clusters. Furthermore, we have identified the unstructured hTDO N- and C-termini as imparting relatively high proteolytic instability, as their deletion (ΔNC) markedly prolonged hTDO t1/2. Additionally, although previous studies reported that upon hepatic heme-depletion, the heme-free apoTDO turns over with a t1/2 ≈ 2.2 h relative to the t1/2 of 7.7 h of holoTDO, mutating the axial heme-ligating His328 to Ala has the opposite effect of prolonging hTDO t1/2. Most importantly, introducing the exosite mutation into the ΔNC-deleted or H328A-mutant completely abolished their prolonged half-lives irrespective of L-Trp presence or absence, thereby revealing that the exosite is the molecular lynchpin that defines L-Trp-mediated TDO induction via protein stabilization.

scholarly journals The ability of enterococci extracted from traditional Carpathian cheese bryndza to produce biologically active substances

2020 ◽  
Vol 3 (3) ◽  
pp. 15-19
Author(s):  
I. I. Kushnir ◽  
O. Y. Tsisaryk ◽  
S. H. Shalovylo ◽  
B. V. Gutyj ◽  
G. V. Kushnir ◽  
...  
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Essential Amino Acid ◽  
Vitamin B1 ◽  
Essential Amino Acids ◽  
B Vitamins ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Vitamin B3 ◽  
Active Substances

The article presents the results of determining the ability of enterococci extracted from traditional Carpathian cheese bryndza to produce biologically active substances, in particular, amino acids, B vitamins and cations (ammonium, potassium, sodium, magnesium, calcium). It was found that the studied strains of enterococci in different quantities synthesized both essential and essential amino acids. Thus, the essential amino acid lysine was found in the cultivation of strains of E. durans SB18, E. durans SB20, in particular, its concentration was significantly increased by 15.6 and 10.4 %, respectively (P < 0.05) compared to the control. A probable increase in the essential amino acid histidine by 20 and 53.3 % (P < 0.05) was detected in the cultivation of only E. faecium SB12 and E. durans SB18. In addition, it was found a probable increase in threonine synthesis by enterococci E. durans SB6 and E. durans SB18, respectively – 33.3 and 39.6 % (P < 0.05). The replacement amino acid serine was able to synthesize strains of E. faecium SB12, E. durans SB18 and E. durans SB20, while its concentration increased by 40.0 (P < 0.001), 30.0 and 35.0 %, respectively < 0.01), and strains of E. durans, SB6, and E. durans SB18 synthesized glycine, the concentration of which increased by – 10.2 and 16.2 %, respectively (P < 0.01). In addition, it was found that the studied strains in small quantities synthesized B vitamins, or not synthesized at all. In all experimental samples the most vitamin B1 was detected, its concentration increased from 8.5 to 10.0 times (P < 0.001). Riboflavin was synthesized by three strains of enterococci – E. durans SB6, E. durans SB18, E. durans SB20, so the concentration of vitamin B2 probably increased, respectively, 4.1, 2.0 and 2.0 times (P < 0.05). Enterococci E. durans SB6, E. faecium SB12, E. durans SB18 and E. durans SB20 synthesized in significant quantities only vitamin B3, in particular, its concentration probably increased by 1.5, 1.5 (P < 0.05), respectively, 1.5 (P < 0.01) and 1.6 (P < 0.001) times, and vitamin B5 was produced by E. faecium SB12, E. durans SB18 and E. durans SB20, the concentration of nicotinic acid increased, respectively, 2.9 (P < 0.05), 8.4 and 9.5 (P < 0.001) times. Analysis of the macroelement composition of the supernatant of enterococci showed that strains of E. durans, SB6, E. faecium SB12, E. durans SB18 and E. durans SB20 are able to produce only Calcium, in particular, found a probable increase, respectively, in 1.8, 2.4, 1.6 and 1.4 times (P < 0.05).

scholarly journals Importance of Branched-Chain Amino Acid Utilization in Francisella Intracellular Adaptation

2014 ◽  
Vol 83 (1) ◽  
pp. 173-183 ◽  
Author(s):  
Gael Gesbert ◽  
Elodie Ramond ◽  
Fabiola Tros ◽  
Julien Dairou ◽  
Eric Frapy ◽  
...  
Keyword(s):  
Amino Acid ◽  
Critical Role ◽  
Cell Types ◽  
Host Cells ◽  
Metabolic Adaptation ◽  
Amino Acid Transporters ◽  
Loss Of Function ◽  
Content Type ◽  
Branched Chain Amino Acid ◽  
Branched Chain

Intracellular bacterial pathogens have adapted their metabolism to optimally utilize the nutrients available in infected host cells. We recently reported the identification of an asparagine transporter required specifically for cytosolic multiplication ofFrancisella. In the present work, we characterized a new member of the major super family (MSF) of transporters, involved in isoleucine uptake. We show that this transporter (here designated IleP) plays a critical role in intracellular metabolic adaptation ofFrancisella. Inactivation of IleP severely impaired intracellularF. tularensissubsp.novicidamultiplication in all cell types tested and reduced bacterial virulence in the mouse model. To further establish the importance of theilePgene inF. tularensispathogenesis, we constructed a chromosomal deletion mutant ofileP(ΔFTL_1803) in theF. tularensissubsp.holarcticalive vaccine strain (LVS). Inactivation of IleP in theF. tularensisLVS provoked comparable intracellular growth defects, confirming the critical role of this transporter in isoleucine uptake. The data presented establish, for the first time, the importance of isoleucine utilization for efficient phagosomal escape and cytosolic multiplication ofFrancisellaand suggest that virulentF. tularensissubspecies have lost their branched-chain amino acid biosynthetic pathways and rely exclusively on dedicated uptake systems. This loss of function is likely to reflect an evolution toward a predominantly intracellular life style of the pathogen. Amino acid transporters should be thus considered major players in the adaptation of intracellular pathogens.

scholarly journals Interrelationships between biotin, choline and other B-vitamins and the occurrence of fatty liver and kidney syndrome and sudden death syndrome in broiler chickens

1982 ◽  
Vol 48 (1) ◽  
pp. 177-184 ◽  
Author(s):  
C. C. Whitehead ◽  
C. J. Randall
Keyword(s):  
Sudden Death ◽  
Fatty Liver ◽  
Broiler Chickens ◽  
Dietary Supplementation ◽  
B Vitamins ◽  
Sudden Death Syndrome ◽  
Post Mortem ◽  
Deficient Diet ◽  
Liver And Kidney ◽  
B Vitamin

1. Addition of supplemental choline to a biotin-deficient diet decreased the biotin status of chicks and increased mortality from fatty liver and kidney syndrome (FLKS).2. Mortality was also increased by dietary supplementation with a mixture of other B-vitamins, excluding biotin, and was highest when the choline and B-vitamin supplements were combined.3. The occurrence of sudden death syndrome (SDS) was unaffected by dietary biotin concentration.4. A previously unreported condition was observed in which birds died showing post-mortem signs characteristic of both FLKS and SDS and whose occurrence was related to the biotin status of the chicks.

Dietary intake of tryptophan tied emotion-related impulsivity in humans

2019 ◽  
pp. 1-8 ◽  
Author(s):  
Florian Javelle ◽  
Descartes Li ◽  
Philipp Zimmer ◽  
Sheri L. Johnson
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Food Intake ◽  
Essential Amino Acid ◽  
Food Habits ◽  
Psychological Disorder ◽  
Serotonin Synthesis ◽  
Amino Acid Tryptophan ◽  
Pass Through ◽  
Three Factor

Abstract. Emotion-related impulsivity, defined as the tendency to say or do things that one later regret during periods of heightened emotion, has been tied to a broad range of psychopathologies. Previous work has suggested that emotion-related impulsivity is tied to an impaired function of the serotonergic system. Central serotonin synthesis relies on the intake of the essential amino acid, tryptophan and its ability to pass through the blood brain barrier. Objective: The aim of this study was to determine the association between emotion-related impulsivity and tryptophan intake. Methods: Undergraduate participants (N = 25, 16 women, 9 men) completed a self-rated measure of impulsivity (Three Factor Impulsivity Index, TFI) and daily logs of their food intake and exercise. These data were coded using the software NutriNote to evaluate intakes of tryptophan, large neutral amino acids, vitamins B6/B12, and exercise. Results: Correlational analyses indicated that higher tryptophan intake was associated with significantly lower scores on two out of three subscales of the TFI, Pervasive Influence of Feelings scores r =  –.502, p < . 010, and (lack-of) Follow-Through scores, r =  –.407, p < . 050. Conclusion: Findings provide further evidence that emotion-related impulsivity is correlated to serotonergic indices, even when considering only food habits. It also suggests the need for more research on whether tryptophan supplements might be beneficial for impulsive persons suffering from a psychological disorder.

QTL Mapping and Analysis Based on Embryo and Maternal Genetic Systems for Semi-Essential Amino Acid Contents in Rapeseed (Brassica napusL.)

2015 ◽  
Vol 41 (1) ◽  
pp. 57
Author(s):  
Juan WEN ◽  
Jian-Feng XU ◽  
Yan LONG ◽  
Hai-Ming XU ◽  
Jin-Ling MENG ◽  
...  
Keyword(s):  
Amino Acid ◽  
Qtl Mapping ◽  
Essential Amino Acid ◽  
Genetic Systems ◽  
Amino Acid Contents

scholarly journals 88 Benefits of increasing amino acid intake in late gestation in prolific sows

2020 ◽  
Vol 98 (Supplement_3) ◽  
pp. 76-76
Author(s):  
Ron Ball ◽  
Crystal L Levesque ◽  
D J Cadogan
Keyword(s):  
Birth Weight ◽  
Amino Acid ◽  
Reproductive Performance ◽  
Essential Amino Acid ◽  
Control Diet ◽  
Genetic Selection ◽  
Late Gestation ◽  
Negative Effects ◽  
Amino Acid Levels ◽  
The Many

Abstract Most sows are fed a constant energy and amino acid supply throughout gestation, in line with the recommendations of most authorities and swine genetic companies. These recommendations for sow feeding have seen little change in decades, despite the many ways that sows have changed dramatically in reproductive performance. Beginning in about the year 2000, sow litter size has steadily increased as a result of genetic selection. With this increase in litter number has been a steady decline in birth weight, and the resulting negative effects of lower birthweight on subsequent piglet performance. Many experiments using so-called ‘bump’ feeding, or increased energy intake in late gestation, have been conducted in attempts to arrest this decline in birthweight and piglet performance. Generally, these experiments have shown little to no improvement in birthweight and often have negative effects on sow feed intake during gestation. These experiments have ignored the fact that the energy:amino acid ratios (lysine, threonine, isoleucine, tryptophan) in late gestation are different than during early and mid-gestation. In recent research in Australia we hypothesised that rapidly increasing essential amino acid levels in late gestation would increase birth weight and potentially improve subsequent reproductive performance. Three hundred and thirty-four multiparous PIC sows (average parity 3.6, average LW 261 kg) were housed in a dynamic gestation pen after mating and randomly assigned to one of two diet regimes. Two 13.5 MJ/kg DE gestation diets were formulated and created by blending in an ESF. The Control diet contained 0.48 g SID lysine per MJ DE and SID threonine, methionine+ cysteine, isoleucine and tryptophan at 68%, 65%, 58% and18% of SID lysine and offered at 2.2kg/day from d 28 to d 110. Sow were then moved to the farrowing house and placed on a lactation diet at 3.5kg/d. The Treatment diet contained 0.55 g SID lysine/MJ DE and SID threonine, methionine+cysteine, isoleucine and tryptophan at 78%, 65%, 60% and 20% of SID lysine and offered at 2.1kg/d from d 28 to d 85 and then increased to 2.4 kg/d to d 110 d. Increasing essential amino acid levels in late gestation increased gestational weight gain (5.6 kg, P=0.004), increased total litter birth weight (1.25 kg, P=0.003), and increased the birthweight of liveborn pigs from 1.286 to 1.329 kg, (P=0.04). There was no significant effect on the total number born or born alive. Piglet performance is not available because this commercial farm practices cross-fostering. Effects of continuation of this feeding regime in the same sows during subsequent parities is currently being evaluated.

scholarly journals Arginine becomes an essential amino acid after massive resection of rat small intestine.

1994 ◽  
Vol 269 (51) ◽  
pp. 32667-32671
Author(s):  
Y. Wakabayashi ◽  
E. Yamada ◽  
T. Yoshida ◽  
H. Takahashi
Keyword(s):  
Small Intestine ◽  
Amino Acid ◽  
Essential Amino Acid ◽  
Rat Small Intestine ◽  
Massive Resection

scholarly journals Codon harmonization reduces amino acid misincorporation in bacterially expressed P. falciparum proteins and improves their immunogenicity

AMB Express ◽  
2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Neeraja Punde ◽  
Jennifer Kooken ◽  
Dagmar Leary ◽  
Patricia M. Legler ◽  
Evelina Angov
Keyword(s):  
Protein Structure ◽  
Amino Acid ◽  
Codon Usage ◽  
Dna Sequences ◽  
Structural Integrity ◽  
Host Cells ◽  
Loss Of Function ◽  
Species Specific ◽  
And Function ◽  
The Impact

Abstract Codon usage frequency influences protein structure and function. The frequency with which codons are used potentially impacts primary, secondary and tertiary protein structure. Poor expression, loss of function, insolubility, or truncation can result from species-specific differences in codon usage. “Codon harmonization” more closely aligns native codon usage frequencies with those of the expression host particularly within putative inter-domain segments where slower rates of translation may play a role in protein folding. Heterologous expression of Plasmodium falciparum genes in Escherichia coli has been a challenge due to their AT-rich codon bias and the highly repetitive DNA sequences. Here, codon harmonization was applied to the malarial antigen, CelTOS (Cell-traversal protein for ookinetes and sporozoites). CelTOS is a highly conserved P. falciparum protein involved in cellular traversal through mosquito and vertebrate host cells. It reversibly refolds after thermal denaturation making it a desirable malarial vaccine candidate. Protein expressed in E. coli from a codon harmonized sequence of P. falciparum CelTOS (CH-PfCelTOS) was compared with protein expressed from the native codon sequence (N-PfCelTOS) to assess the impact of codon usage on protein expression levels, solubility, yield, stability, structural integrity, recognition with CelTOS-specific mAbs and immunogenicity in mice. While the translated proteins were expected to be identical, the translated products produced from the codon-harmonized sequence differed in helical content and showed a smaller distribution of polypeptides in mass spectra indicating lower heterogeneity of the codon harmonized version and fewer amino acid misincorporations. Substitutions of hydrophobic-to-hydrophobic amino acid were observed more commonly than any other. CH-PfCelTOS induced significantly higher antibody levels compared with N-PfCelTOS; however, no significant differences in either IFN-γ or IL-4 cellular responses were detected between the two antigens.

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