• Asian-Australasian Journal of Animal Sciences
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• 제26권10호
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• pp.1416-1423
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• 2013

The metabolomic profile of the anaerobic fungus Piromyces sp. F1, isolated from the rumen of goats, and how this is affected by the presence of naturally associated methanogens, was analyzed by nuclear magnetic resonance spectroscopy. The major metabolites in the fungal monoculture were formate, lactate, ethanol, acetate, succinate, sugars/amino acids and ${\alpha}$-ketoglutarate, whereas the co-cultures of anaerobic fungi and associated methanogens produced citrate. This is the first report of citrate as a major metabolite of anaerobic fungi. Univariate analysis showed that the mean values of formate, lactate, ethanol, citrate, succinate and acetate in co-cultures were significantly higher than those in the fungal monoculture, while the mean values of glucose and ${\alpha}$-ketoglutarate were significantly reduced in co-cultures. Unsupervised principal components analysis revealed separation of metabolite profiles of the fungal mono-culture and co-cultures. In conclusion, the novel finding of citrate as one of the major metabolites of anaerobic fungi associated with methanogens may suggest a new yet to be identified pathway exists in co-culture. Anaerobic fungal metabolism was shifted by associated methanogens, indicating that anaerobic fungi are important providers of substrates for methanogens in the rumen and thus play a key role in ruminal methanogenesis.

• Journal of Animal Science and Technology
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• 제62권2호
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• pp.121-140
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• 2020

Anaerobic fungi habitat in the gastrointestinal tract of foregut fermenters or hindgut fermenters and degrade fibrous plant biomass through the hydrolysis reactions with a wide variety of cellulolytic enzymes and physical penetration through fiber matrix with their rhizoids. To date, seventeen genera have been described in family Neocallimasticaceae, class Neocallimastigomycetes, phylum Neocallimastigomycota and one genus has been described in phylum Neocallimastigomycota. In National Center for Biotechnology Information (NCBI) database (DB), 23,830 nucleotide sequences and 59,512 protein sequences have been deposited and most of them were originated from Piromyces, Neocallimastix and Anaeromyces. Most of protein sequences (44,025) were acquired with PacBio next generation sequencing system. The whole genome sequences of Anaeromyces robustus, Neocallimastix californiae, Pecoramyces ruminantium, Piromyces finnis and Piromyces sp. E2 are available in Joint Genome Institute (JGI) database. According to the results of protein prediction, average Isoelectric points (pIs) were ranged from 5.88 (Anaeromyces) to 6.57 (Piromyces) and average molecular weights were ranged from 38.7 kDa (Orpinomyces) to 56.6 kDa (Piromyces). In Carbohydrate-Active enZYmes (CAZY) database, glycoside hydrolases (36), carbohydrate binding module (11), carbohydrate esterases (8), glycosyltransferase (5) and polysaccharide lyases (3) from anaerobic fungi were registered. During four decades, 1,031 research articles about anaerobic fungi were published and 444 and 719 articles were available in PubMed (PM) and PubMed Central (PMC) DB.

• Asian-Australasian Journal of Animal Sciences
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• 제10권6호
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• pp.541-550
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• 1997

Anaerobic chytridiomycete fungi are now well recognized as one of the major components of rumen microflora. Since the discovery of anaerobic fungi, the knowledge upon their morphology and physiology has been accumulated. It is certain that they gave roles in ruminal fiber digestion, although their quantitative contribution to rumen digestion is still unclear. Their role in fiber digestion is complicated by the dietary factors and the interaction with other microorganisms. We aim at reviewing such information in this article. Considerable attention gas been paid to the polysaccharidase of these fungi. Analysis on the fungal genes encoding these enzymes has been performed in several laboratories. This article also covers the genetical analysis of fungal polysaccharidases.

• Asian-Australasian Journal of Animal Sciences
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• 제20권1호
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• pp.70-74
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• 2007

An in vitro study was carried out to investigate the differences in rumen microbes and fiber degradation capacity between sheep and goats. Three local male sheep and three Inner Mongolia male cashmere goats (aged 1.5 to 2 years; weight 25.0 to 32.0 kg) were each fitted with a permanent rumen cannula used to provide rumen fluid. Cycloheximide was used to eliminate rumen anaerobic fungi. The results showed that the quantities of fungal zoospores in the culture fluid of the control group were significantly greater in the sheep than in the goats; however, bacteria and protozoa counts were significantly higher in goats than in sheep. The digestibility of straw dry matter did not differ significantly between the two species before elimination of fungi, but tended to be higher for sheep (55.4%) than for goats (53.3%). The results also indicated that bacteria counts increased significantly after elimination of anaerobic fungi; however, the digestibility of straw dry matter significantly decreased by 12.1% and 8.6% for sheep and goats respectively. This indicated that the anaerobic fungi of the rumen played an important role in degradation of fiber.

• Journal of Animal Science and Technology
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• 제45권6호
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• pp.1019-1030
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• 2003

본 연구는 국내의 재래 반추동물인 재래산양과 한우의 장내에 서식하며 강력한 섬유소를 분해하는 혐기 곰팡이를 탐색하고 분리하여 섬유소 분해 특성을 구명하고자 실시되었다. 산양의 반추위로부터 16종과 한우의 십이지장 소화물로부터 5종의 혐기 곰팡이를 분리하여 총 21종의 혐기성 곰팡이가 분리되었다. 섬유소 분해효소의 활력을 측정하여 그 중 섬유소 분해력이 높은 4종의 곰팡이에 대하여 광학현미경에 의한 형태학적 관찰을 기초로 동정 작업을 수행하였다. NLRI-M003은 monocentric 성장형태, 구형의 포자낭, filamentous rhizoid 및 유주자의 flagella가 다수인 Neocallimastix sp., NLRI-M014는 monocentric 성장형태, 방추형의 포자낭, filamentous rhizoid 및 유주자의 flagella가 단수인 Piromyces sp.로, NLRI-T004는 monocentric 성장형태, 난형의 포자낭, filamentous rhizoid 및 유주자의 fagella 수가 다수인 Neocallimastix sp.로 각각 확인되었다. NLRI-M001은 Orpinomyces sp. 와 유사한 것으로 추측되나 지금까지 밝혀진 곰팡이 이외에 다른 밝혀지지 않은 곰팡이가 존재할 가능성이 있을 것으로 평가되어 더욱 더 세부적인 조사가 필요하다고 사료되었다. 혐기 곰팡이의 섬유소 분해 특성을 조사하기 위해 산양의 반추위로부터 분리된 NLRI-M003 혐기 곰팡이 배양액을 2% 첨가하여 혼합 반추위 미생물의 in vitro 건물 분해율을 볏짚과 filter paper를 기질로 하여 조사하였다. 모든 처리구에서 혐기 곰팡이 배양액을 첨가한 첨가구가 무첨가구에 비하여 볏짚의 경우 약 4%이상(p〈0.05) 그리고 filtre paper를 기질로 사용시 11% 이상(p〈0.001)의 분해율이 증가하였다. 또한 CMCase와 xylanase 효소의 활력도 첨가구에서 증가하였으며 특히 반추위 곰팡이는 강력한 xylanase 효소활력이 높음을 보여주었다.

• Asian-Australasian Journal of Animal Sciences
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• 제13권1호
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• pp.23-30
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• 2000

The effects of grass lipids and long chain fatty acids (LCFA; palmitic, stearic and oleic acids), at low concentrations (0.001~0.02%), on the growth and enzyme activity of two strains of anaerobic fungi, monocentric strain Piromyces rhizinflata B157 and polycentric strain Orpinomyces joyonii SG4, were investigated. The addition of grass lipids to the medium significantly (p<0.05) decreased filter paper (FP) cellulose digestion, cellulase activity and fungal growth compared to control treatment. However, LCFA did not have any significant inhibitory effects on fungal growth and enzyme activity, which, however, were significantly (p<0.05) stimulated by the addition of oleic acid as have been observed in rumen bacteria and protozoa. This is the first report to our knowledge on the effects of LCFA on the rumen anaerobic fungi. Continued work is needed to identify the mode of action of LCFA in different fungal strains and to verify whether these microorganisms have ability to hydrogenate unsaturated fatty acids to saturated fatty acids.

• Asian-Australasian Journal of Animal Sciences
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• 제14권7호
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• pp.941-946
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• 2001

The effects of various concentrations of saturated fatty acids (SFA; caprylic, capric and stearic acids) on the growth of the anaerobic fungus, Neocallimastix frontalis C5-1 isolated from the rumen of a Korean native goat were investigated. At higher concentrations of fatty acids (0.1%, w/v), the addition of SFA strongly decreased filter paper (FP) cellulose digestion and polysaccharide-degrading enzyme activity. The sensitivity of the rumen anaerobic fungus to the added fatty acids increased in the following order: caprylic ($C_{8:0}$)>capric($C_{10:0}$)>stearic($C_{18:0}$) acid, although stearic acid had no significant (p<0.05) inhibitory effects at any of the concentrations tested. However, the addition of SFA at lower concentrations (0.01 and 0.001% levels), did not inhibit FP cellulose degradation and enzyme activity. Furthermore, although these parameters were slightly stimulated by the addition of SFA, they were not statistically different from control values. This is the first report examining the effects of fatty acids on anaerobic gut fungi. We found that the lower levels of fatty acids used in this experiment were able to stimulate the growth and specific enzyme activities of rumen anaerobic fungi, whereas the higher levels of fatty acids were inhibitory with respect to fungal cellulolysis.

• Asian-Australasian Journal of Animal Sciences
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• 제22권11호
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• pp.1555-1565
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• 2009

Anaerobic rumen fungi have been regarded as good genetic resources for enzyme production which might be useful for feed supplements, bio-energy production, bio-remediation and other industrial purposes. In this study, an expressed sequence tag (EST) library of the rumen anaerobic fungus Neocallimastix frontalis was constructed and functional genes from the EST library were analyzed to elucidate carbohydrate metabolism of anaerobic fungi. From 10,080 acquired clones, 9,569 clones with average size of 628 bp were selected for analysis. After the assembling process, 1,410 contigs were assembled and 1,369 sequences remained as singletons. 1,192 sequences were matched with proteins in the public data base with known function and 693 of them were matched with proteins isolated from fungi. One hundred and fifty four sequences were classified as genes related with biological process and 328 sequences were classified as genes related with cellular components. Most of the enzymes in the pathway of glucose metabolism were successfully isolated via construction of 10,080 ESTs. Four kinds of hemi-cellulase were isolated such as mannanase, xylose isomerase, xylan esterase, and xylanase. Five $\beta$-glucosidases with at least three different conserved domain structures were isolated. Ten cellulases with at least five different conserved domain structures were isolated. This is the first solid data supporting the expression of a multiple enzyme system in the fungus N. frontalis for polysaccharide hydrolysis.

• Asian-Australasian Journal of Animal Sciences
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• 제12권1호
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• pp.104-112
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• 1999

Since the anaerobic rumen fungi were discovered in the rumen of a sheep over two decades ago, they have been reported in a wide range of herbivores fud on high fibre diets. The extensive colonisation and degradation of fibrous plant tissues by the fungi suggest that they have a role in fibre digestion. All rumen fungi studied so far are fibrolytic. They produce a range of hydrolytic enzymes, which include the cellulases, hemicellulases, pectinases and phenolic acid esterases, to enable them to invade and degrade the lignocellulosic plant tissues. Although rumen fungi may not seem to be essential to general rumen function since they may be absent in animals fed on low fibre diets, they, nevertheless, could contribute to the digestion of high-fibre poor-quality forages.

• Asian-Australasian Journal of Animal Sciences
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• 제2권3호
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• pp.456-457
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• 1989