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Life (Basel, Switzerland) Jan 2024Alpacas, important genetic resources in the Andean region of Peru, are vulnerable to diarrhea caused by pathogenic parasites such as and sp., which can be fatal,...
Alpacas, important genetic resources in the Andean region of Peru, are vulnerable to diarrhea caused by pathogenic parasites such as and sp., which can be fatal, especially in neonates, due to their physiological immaturity and limited adaptability. The study investigated the diversity and abundance of intestinal fungi and protists in alpacas infected with and sp. compared to healthy alpacas. A total of 19 alpacas, aged between one and two months, were included. They were divided into two groups, one with pathological conditions (nine) and the other healthy (ten). Parasitological analyses for the detection of parasites and subsequent molecular analysis were performed on the collected fecal samples. The results revealed a greater diversity and abundance of protists in infected alpacas in comparison with healthy alpacas, while the fungal composition did not show significant changes. Therefore, parasitic infections affect the protist component of the alpaca gut microbiota. Also, it was observed that was identified in all healthy alpacas, serving as a possible marker of the health of the intestinal microbiota; in addition, and are beneficial fungi that help control diseases. This groundbreaking study in neonatal alpacas is the first to explore potential changes in the intestinal microbiota during an infectious state, underscoring the importance of further research to comprehend its effects on alpaca health and immune responses.
PubMed: 38398696
DOI: 10.3390/life14020187 -
Foods (Basel, Switzerland) Jul 2023To study the diversity of microbial flora in Hongqu sufu and analyze the characteristics of special flavor compounds, this study took self-made Hongqu sufu as the...
To study the diversity of microbial flora in Hongqu sufu and analyze the characteristics of special flavor compounds, this study took self-made Hongqu sufu as the research object. Dynamic changes in sufu during fermentation were studied. High-throughput sequencing (HTS) was used to analyze changes in the diversity of fungal and bacterial communities during fermentation. The results showed that at the phylum level, the dominant fungal phyla were identified, Mucormyces and Ascomycetes. The dominant bacterial phyla were Proteobacteria and Firmicutes. At the genus level, the dominant fungal genera were identified as , and . The dominant bacterial genera were , , , and . Headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with technology that can dynamically change flavor compounds was explored to investigate the correlation between microbiota and flavor compounds. In different stages of fermentation, 75 main volatile organic compounds were identified, including seven alcohols, four acids, 16 alkanes, 14 olefins, seven kinds of aldehydes, two kinds of ketones, 10 kinds of esters, one kind of phenol, one kind of sulfur-containing compound, one benzene, and 12 other compounds. The correlation analysis between flora and flavor compounds showed that the fungi genera and were significantly correlated with most flavor compounds. Bacteria genera including , , and had a strong positive correlation with ethyl oleate.
PubMed: 37509892
DOI: 10.3390/foods12142800 -
The Journal of Biological Chemistry Nov 2023Previous research of anion channelrhodopsins (ACRs) has been performed using cytoplasmic domain (CPD)-deleted constructs and therefore have overlooked the native...
Previous research of anion channelrhodopsins (ACRs) has been performed using cytoplasmic domain (CPD)-deleted constructs and therefore have overlooked the native functions of full-length ACRs and the potential functional role(s) of the CPD. In this study, we used the recombinant expression of full-length Guillardia theta ACR1 (GtACR1_full) for pH measurements in Pichia pastoris cell suspensions as an indirect method to assess its anion transport activity and for absorption spectroscopy and flash photolysis characterization of the purified protein. The results show that the CPD, which was predicted to be intrinsically disordered and possibly phosphorylated, enhanced NO transport compared to Cl transport, which resulted in the preferential transport of NO. This correlated with the extended lifetime and large accumulation of the photocycle intermediate that is involved in the gate-open state. Considering that the depletion of a nitrogen source enhances the expression of GtACR1 in native algal cells, we suggest that NO transport could be the natural function of GtACR1_full in algal cells.
Topics: Anions; Channelrhodopsins; Cryptophyta; Ion Transport; Nitrates
PubMed: 37778732
DOI: 10.1016/j.jbc.2023.105305 -
Journal of Animal Science and... Jul 2023Alginate oligosaccharide (AOS) holds great potential as a novel feed supplement in farm animals. However, the effects of AOS on chicken health and the underlying...
BACKGROUND
Alginate oligosaccharide (AOS) holds great potential as a novel feed supplement in farm animals. However, the effects of AOS on chicken health and the underlying mechanisms are not fully understood. This study aimed to optimize the enzymatic preparation of AOS by using bacterial alginate lyases expressed in yeast, investigate the effects of the prepared AOS on the growth performance and gut health of broiler chickens, and reveal the underlying mechanisms.
RESULTS
Five alginate lyases from bacteria were cloned into Pichia pastoris GS115 and the alginate lyase PDE9 was expressed at relatively high yield, activity and stability in P. pastoris. Animal trials were carried out using 320 1-day-old male Arbor Acres broilers (four groups; 8 replicates/group × 10 chicks/replicate) receiving either a basal diet or the same diet supplemented with 100, 200 and 400 mg/kg PDE9-prepared AOS for 42 d. The results showed that dietary supplementation of 200 mg/kg AOS displayed the highest activity in promoting the birds' ADG and ADFI (P < 0.05). AOS ameliorated the intestinal morphology, absorption function and barrier function, as indicated by the enhanced (P < 0.05) intestinal villus height, maltase activity, and the expression of PEPT, SGLT1, ZNT1, and occludin. AOS also increased serum insulin-like growth factor-1, ghrelin (P < 0.05), and growth hormone (P < 0.1). Moreover, the concentrations of acetate, isobutyrate, isovalerate, valerate, and total SCFAs in cecum of birds fed AOS were significantly higher than the control birds (P < 0.05). Metagenomic analysis indicated that AOS modulated the chicken gut microbiota structure, function, and microbial interactions and promoted the growth of SCFAs-producing bacteria, for example, Dorea sp. 002160985; SCFAs, especially acetate, were found positively correlated with the chicken growth performance and growth-related hormone signals (P < 0.05). We further verified that AOS can be utilized by Dorea sp. to grow and to produce acetate in vitro.
CONCLUSIONS
We demonstrated that the enzymatically produced AOS effectively promoted broiler chicken growth performance by modulating the chicken gut microbiota structure and function. For the first time, we established the connections among AOS, chicken gut microbiota/SCFAs, growth hormone signals and chicken growth performance.
PubMed: 37394467
DOI: 10.1186/s40104-023-00887-4 -
International Journal of Molecular... Jul 2023The brown planthopper (Stål) (BPH) is a typical monophagous sucking rice pest. Over the course of their evolution, BPH and its symbionts have established an...
The brown planthopper (Stål) (BPH) is a typical monophagous sucking rice pest. Over the course of their evolution, BPH and its symbionts have established an interdependent and mutually beneficial relationship, with the symbionts being important to the growth, development, reproduction, and variation in virulence of BPH. Yeast-like symbionts (YLS), harbored in the abdomen fat body cells of BPH, are vital to the growth and reproduction of the host. In recent research, the symbionts in BPH have mainly been detected using blood cell counting, PCR, real-time quantitative PCR, and other methods. These methods are vulnerable to external interference, cumbersome, time consuming and laborious. Droplet digital PCR (ddPCR) does not need a standard curve, can achieve absolute quantification, does not rely on Cq values, and is more useful for analyzing copy number variation, gene mutations, and relative gene expression. A rapid detection method for the YLS of BPH based on ddPCR was established and optimized in this study. The results showed that the method's limits of detection for the two species of YLS ( symbionts and ) were 1.3 copies/μL and 1.2 copies/μL, respectively. The coefficient of variation of the sample repetition was less than 5%; therefore, the ddPCR method established in this study had good sensitivity, specificity, and repeatability. It can be used to detect the YLS of BPH rapidly and accurately.
Topics: Animals; Ascomycota; DNA Copy Number Variations; Hemiptera; Oryza; Real-Time Polymerase Chain Reaction
PubMed: 37446249
DOI: 10.3390/ijms241311071 -
International Journal of Molecular... Nov 2023and , the most frequently isolated candidiasis species in the world, have developed mechanisms of resistance to treatment with azoles. Among the clinically used...
and , the most frequently isolated candidiasis species in the world, have developed mechanisms of resistance to treatment with azoles. Among the clinically used antifungal drugs are statins and other compounds that inhibit 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), resulting in decreased growth and ergosterol levels in yeasts. Ergosterol is a key element for the formation of the yeast cell membrane. However, statins often cause DNA damage to yeast cells, facilitating mutation and drug resistance. The aim of the current contribution was to synthesize seven series of compounds as inhibitors of the HMGR enzyme of ssp., and to evaluate their effect on cellular growth, ergosterol synthesis and generation of mutants of and Compared to the reference drugs (fluconazole and simvastatin), some HMGR inhibitors caused lower growth and ergosterol synthesis in the yeast species and generated fewer mutants. Moreover, heterologous expression was achieved in , and compounds , , and inhibited the activity of recombinant CgHMGR and showed better binding energy values than for α-asarone and simvastatin. Thus, we believe these are good candidates for future antifungal drug development.
Topics: Hydroxymethylglutaryl-CoA Reductase Inhibitors; Candida albicans; Candida glabrata; Antifungal Agents; Simvastatin; Hydroxymethylglutaryl-CoA-Reductases, NADP-dependent; Oxidoreductases; Ergosterol; Microbial Sensitivity Tests
PubMed: 38069194
DOI: 10.3390/ijms242316868 -
International Journal of Molecular... Jan 2024Sterols exert a profound influence on numerous cellular processes, playing a crucial role in both health and disease. However, comprehending the effects of sterol...
Sterols exert a profound influence on numerous cellular processes, playing a crucial role in both health and disease. However, comprehending the effects of sterol dysfunction on cellular physiology is challenging. Consequently, numerous processes affected by impaired sterol biosynthesis still elude our complete understanding. In this study, we made use of yeast strains that produce cholesterol instead of ergosterol and investigated the cellular response mechanisms on the transcriptome as well as the lipid level. The exchange of ergosterol for cholesterol caused the downregulation of phosphatidylethanolamine and phosphatidylserine and upregulation of phosphatidylinositol and phosphatidylcholine biosynthesis. Additionally, a shift towards polyunsaturated fatty acids was observed. While the sphingolipid levels dropped, the total amounts of sterols and triacylglycerol increased, which resulted in 1.7-fold enlarged lipid droplets in cholesterol-producing yeast cells. In addition to internal storage, cholesterol and its precursors were excreted into the culture supernatant, most likely by the action of ABC transporters Snq2, Pdr12 and Pdr15. Overall, our results demonstrate that, similarly to mammalian cells, the production of non-native sterols and sterol precursors causes lipotoxicity in , mainly due to upregulated sterol biosynthesis, and they highlight the different survival and stress response mechanisms on multiple, integrative levels.
Topics: Animals; Humans; Sterols; Saccharomyces cerevisiae; Phytosterols; Ergosterol; Cholesterol; Mammals
PubMed: 38255855
DOI: 10.3390/ijms25020781 -
Bioresource Technology Sep 2023In this study, α-L-arabinofuranosidase (AF) from Aspergillus awamori was heterologously expressed in Pichia pastoris X33, with a 1-fold increase in AF activity after...
In this study, α-L-arabinofuranosidase (AF) from Aspergillus awamori was heterologously expressed in Pichia pastoris X33, with a 1-fold increase in AF activity after codon and vector optimization. AF remained stable at 60-65 °C and displayed a broad pH stability range of 2.5-8.0. It also demonstrated considerable resistance to pepsin and trypsin. Furthermore, compared with xylanase alone, AF with xylanase exhibited a marked synergistic effect in the degradation of expanded corn bran, corn bran, and corn distillers' dried grains with solubles, reducing sugars by 3.6-fold, 1.4-fold, and 6.5-fold, respectively, with the degree of synergy increasing to 4.61, 2.44, and 5.4, respectively, while in vitro dry matter digestibility values were 17.6%, 5.2%, and 8.8%, respectively. After enzymatic saccharification, corn byproducts were converted to prebiotic xylo-oligosaccharides and arabinoses, thereby demonstrating the favorable properties of AF in the degradation of corn biomass and its byproducts.
Topics: Zea mays; Glycoside Hydrolases; Aspergillus
PubMed: 37290707
DOI: 10.1016/j.biortech.2023.129278 -
Current Research in Food Science 2024The current study investigated the probiotic potential of yeast isolated from kombucha, a tea beverage fermented with a symbiotic culture of acetic acid bacteria and...
The current study investigated the probiotic potential of yeast isolated from kombucha, a tea beverage fermented with a symbiotic culture of acetic acid bacteria and yeast. A total of 62 yeast strains were previously isolated from four different commercial kombucha samples sold in New Zealand. Fifteen representative isolates belonging to eight different species were evaluated for their growth under different conditions (temperature, low pH, concentrations of bile salts, and NaCl). Cell surface characteristics, functional and enzymatic activities of the selected strains were also studied in triplicate experiments. Results showed that six strains ( LBY1, LBY5, DOY1, DOY8, GBY1, and GBY2) were able to grow under low-acid conditions (at pH 2 and pH 3) and in the presence of bile salts. This suggests their potential to survive passage through the human gut. All 15 strains exhibited negative enzymatic activity reactions (haemolytic, gelatinase, phospholipase, and protease activities), and thus, they can be considered safe to consume. Notably, two of the fifteen strains ( GBY1 and GBY2) exhibited desirable cell surface hydrophobicity (64.60-83.87%), auto-aggregation (>98%), co-aggregation, resistance to eight tested antibiotics (ampicillin, chloramphenicol, colistin sulphate, kanamycin, nalidixic acid, nitrofurantoin, streptomycin, and tetracycline), and high levels of antioxidant activities (>90%). Together, our data reveal the probiotic activities of two yeast strains GBY1 and GBY2 and their potential application in functional food production.
PubMed: 38524400
DOI: 10.1016/j.crfs.2024.100711 -
Frontiers in Microbiology 2023While the variation in physicochemical parameters, microbial communities, metabolism, composition, and the proportion of volatile components in fermented grains (FG)...
INTRODUCTION
While the variation in physicochemical parameters, microbial communities, metabolism, composition, and the proportion of volatile components in fermented grains (FG) affect final Baijiu quality, their complex interactions during the ultra-long fermentation of compound-flavor Baijiu (CFB) are still poorly understood.
METHODS
In this study, amplicon sequencing was used to analyze the microbial community, and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used to analyze the volatile components in FG during ultra-long fermentation of CFB. The relationships between the dominant microbial communities, physicochemical parameters, and volatile components were analyzed using redundancy analysis and network analysis.
RESULTS
During ultra-long fermentation, bacterial diversity was initially higher than during the mid and late stages. Fungal diversity in the mid stages was higher than that initially and later in the process. A total of 88 volatile components, including six alcohols, 43 esters, eight aldehydes and ketones, 13 acids, and 18 other compounds were detected in FG. Starch and reducing sugars in FG strongly affected the composition and function of bacterial and fungal communities. However, acidity had little effect on the composition and function of the bacterial flora. , and were the core microbial genera involved in metabolizing the volatile components of FG.
DISCUSSION
We provide insights into the relationships and influences among the dominant microbial communities, physicochemical parameters, and volatile components during ultra-long fermentation of CFB. These insights help clarify the fermentation mechanisms of solid-state fermentation Baijiu (SFB) and control and improve the aroma quality of CFB.
PubMed: 37965554
DOI: 10.3389/fmicb.2023.1272559