RESEARCH OF AMYLOLYTIC ACTIVITY OF CULTURAL LIQUIDS IN BIOTECHNOLOGY OF SYMBIOTIC CROPS МЕDUSOMYCES GISEVII AND ORYZAMYCES INDICI

Based on the literature review found that the natural symbionts Medusomyces gisevii and Oryzamyces indici biotechnology are a valuable objects. It is urgent to find ways to impact on it in order to obtain these or other products of its life activity. At present, it is urgent to search for microorganisms producing enzymes, including amylase. One of the most promising in terms of biological objects is a natural microbial symbiont Medusomyces Gisevii (tea fungus) and Oryzamyces Indici, which, thanks to the not identical, microbiological composition and different growing conditions may have a different composition of metabolites. Studies of the amylolytic activity of the culture liquid Medusomyces Gisevii and Oryzamyces indici with different cultivation periods have been carried out. Cultivation of the fungus was carried out in the laboratory according to the classic method. The optimal concentration of sucrose for Medusomyces Gisevii and Oryzamyces Indici biomass growth was set at 5%. Sucrose concentration of 15% and above is not recommended for use due to inhibition of biomass growth with increasing concentration of carbohydrates in the culture medium. It is established that these symbionts start to show the amylolytic activity already on the 10th day of cultivation cultivation in standard nutrient medium, medium supplemented with 10 % milk and serum-based medium and stores it in the course of the experiment (30 days). Over time the amylolytic activity increases. However, the intensity of metabolism of the microorganisms, the criterion of which is the ratio of the total and exogenous amylase is most pronounced in the early stages of cultivation. It was found that the culture medium of polycultures shows high amylolytic activity. This fact allows us to consider the Medusomyces Gisevii and Oryzamyces Indici inoculum as a promising biotechnological raw material source of amylase enzyme.

The multidimensional nutritional niche of fungus-cultivar provisioning in free-ranging colonies of a neotropical leafcutter ant

The foraging trails of Atta leafcutter colonies are among the most iconic scenes in Neotropical ecosystems, with thousands of ants carrying freshly cut plant fragments back to their nests where they are used to provision a fungal food crop. We tested a hypothesis that the fungal cultivar’s multidimensional requirements for macronutrients (protein and carbohydrates) and minerals (Al, Ca, Cu, Fe, K, Mg, Mn, Na, P and Zn) govern the foraging breadth of Atta colombica leafcutter ants in a Panamanian rainforest. Analyses of freshly cut plant fragments carried by leafcutter foragers showed that the combination of fruits, flowers, and leaves provide for a broad realized nutritional niche that can maximize cultivar’s performance. And, while the leaves that comprised the most harvested resource also delivered an intake target containing protein in excess of the amounts that can maximize cultivar growth, in vitro experiments showed that the minerals P, Al, and Fe can enhance the cultivar’s tolerance to protein-biased substrates, and potentially expand the ants’ foraging niche. Yet, the cultivar also exhibits narrow margins between mineral limitation and toxicity that may render plant fragments with seemingly optimal blends of macronutrients unsuitable for provisioning. Our approach highlights that optimal foraging is inherently multidimensional and links the foraging behavior of a generalist insect herbivore to the fundamental nutritional niche of its microbial symbiont.Significance StatementColonies of Atta colombica leafcutter ants can contain millions of specialized workers exhibiting large-scale generalist herbivory. Yet, this generalist foraging niche also depends on the poorly understood physiological needs of the ants’ domesticated fungal cultivar. We show the cultivar’s fundamental nutritional niche is broad for carbohydrates but narrower for protein and a suite of minerals, but that the cultivar’s sensitivity to excess protein is also mediated by Al, Fe, and P. More generally, this study decouples the multidimensional foraging strategies that enable a generalist herbivore to navigate a complex nutritional landscape and mix many imbalanced foods to achieve balanced cultivar provisioning.

An agent-based model of adaptation of holobionts with different microbial symbiont transmission modes

ABSTRACTThe hologenome theory suggests that holobionts (host plus symbiont) with hosts that are only able to adapt slowly may be able to persist in deteriorating environmental conditions via rapid adaptation of their microbial symbionts. The effectiveness of such symbiont adaptation may vary depending on whether symbionts are passed directly to offspring (vertical transmission) or acquired from the environment (horizontal transmission). However, it has been suggested that holobionts with horizontal transmission cannot pass down their symbionts faithfully, preventing adaptation at the holobiont level because of host-symbiont disassociation between generations. Here we used an agent-based model to investigate whether holobionts with horizontal microbial symbiont transmission can adapt to increasing stress solely through symbiont adaptation and compared their adaptation to holobionts with vertical transmission. We found that holobionts with either transmission mode were able to adapt to increasing abiotic stress solely via symbiont adaptation. Moreover, those with horizontal transmission were more competitive than those with vertical transmission when hosts were able to selectively associate with the most suitable symbionts. However, those with horizontal transmission were less competitive than those with vertical transmission when symbiont establishment was random. Our results support the hologenome theory and demonstrate that holobionts with horizontal microbial symbiont transmission could adapt to increasing abiotic stress via their symbionts. We also showed that whether holobionts with horizontal or vertical symbiont transmission are favored in increasingly stressful conditions depends on the ability of hosts to recognize and foster microbial symbionts that confer stress tolerance.IMPORTANCESymbiotic organisms such as reef building corals are sensitive to environmental perturbations due to anthropogenic disturbances or climate change, and it is critical to understand whether they are able to adapt to previously unfavorable conditions. To date, studies have focused on the impacts of existing microbial symbiont variation on holobiont stress tolerance but here we use agent-based models to explore holobiont adaptation via symbiont adaptation. We studied both deterministic and stochastic processes in holobiont adaptation by investigating the following four factors: holobiont transmission modes, a host’s ability to recognize tolerance-conferring symbionts, a symbiont’s mutational variance, and rate of stress increase. Our simulation provides a comprehensive understanding of holobiont adaptation under stress, which not only has implications for future endangered symbiotic species management, but also provides fresh insight into species evolution as proposed by the hologenome theory.

Diversity of endophytic and rhizosphere bacteria from pineapple (Ananas comosus) plant in semi-arid ecosystem

Putrie RFW, Aryantha INP, Iriawati, Antonius S. 2020. Diversity of endophytic and rhizosphere bacteria from pineapple (Ananas comosus) plant in semi-arid ecosystem. Biodiversitas 21: 3084-3093. The natural environment majorly influences plant microbiome diversity, in terms of endophytic and rhizobacteria. Pineapple (Ananas comosus L. Merr) has been identified as one of host plants with a capacity to grow in semiarid ecosystems. The intrinsic microbial symbiont composition is recognized in a specific ecological niche. The scientific information available is limited to the inoculants' ability to reduce plant stress, although the diversity in a semiarid ecosystem has not been studied. The aim of this research is to investigate the diversity of endophytic and rhizosphere bacteria obtained from pineapple in a semiarid ecosystem. A total of 117 culturable microbial isolates, dominated by Gram-positive bacteria were obtained from pineapple (88) and rhizosphere (29). The metagenomic analysis showed higher diversity and abundance in rhizospheres compared to the endophytes. Actinobacterium was identified as the most populated colony, while Proteobacterium was more prominent in the host plant. The Bacillus genera were recognized as the dominant symbiont genus. Therefore, the culturable isolates were further developed as candidate inoculants for microbe databases. This is expected to be useful in broadening theoretical knowledge.

Soil organic matter attenuates the efficacy of flavonoid-based plant-microbe communication

Plant-microbe interactions are mediated by signaling compounds that control vital plant functions, such as nodulation, defense, and allelopathy. While interruption of signaling is typically attributed to biological processes, potential abiotic controls remain less studied. Here, we show that higher organic carbon (OC) contents in soils repress flavonoid signals by up to 70%. Furthermore, the magnitude of repression is differentially dependent on the chemical structure of the signaling molecule, the availability of metal ions, and the source of the plant-derived OC. Up to 63% of the signaling repression occurs between dissolved OC and flavonoids rather than through flavonoid sorption to particulate OC. In plant experiments, OC interrupts the signaling between a legume and a nitrogen-fixing microbial symbiont, resulting in a 75% decrease in nodule formation. Our results suggest that soil OC decreases the lifetime of flavonoids underlying plant-microbe interactions.

Host–symbiont specificity determined by microbe–microbe competition in an insect gut

Despite the omnipresence of specific host–symbiont associations with acquisition of the microbial symbiont from the environment, little is known about how the specificity of the interaction evolved and is maintained. The bean bug Riptortus pedestris acquires a specific bacterial symbiont of the genus Burkholderia from environmental soil and harbors it in midgut crypts. The genus Burkholderia consists of over 100 species, showing ecologically diverse lifestyles, and including serious human pathogens, plant pathogens, and nodule-forming plant mutualists, as well as insect mutualists. Through infection tests of 34 Burkholderia species and 18 taxonomically diverse bacterial species, we demonstrate here that nonsymbiotic Burkholderia and even its outgroup Pandoraea could stably colonize the gut symbiotic organ and provide beneficial effects to the bean bug when inoculated on aposymbiotic hosts. However, coinoculation revealed that the native symbiont always outcompeted the nonnative bacteria inside the gut symbiotic organ, explaining the predominance of the native Burkholderia symbiont in natural bean bug populations. Hence, the abilities for colonization and cooperation, usually thought of as specific traits of mutualists, are not unique to the native Burkholderia symbiont but, to the contrary, competitiveness inside the gut is a derived trait of the native symbiont lineage only and was thus critical in the evolution of the insect gut symbiont.

Pengaruh Nutrisi Dan Suhu Terhadap Selektivitas Potensi Antibakteri Dari Bakteri Yang Berasosiasi Dengan Spons

The Influence of nutrient and temperature to the antibacterial selectivity of Sponge Associated-Bacteria Production of pharmacological activity by marine microorganism is strongly influenced by nutrition and environmental conditions. In this study would discuss about the influence of several type of media to the production of antibacterial agent by sponge-. associated microorganisms. About 3 sponges tissue Theonella sp, Callispongia sp. and Lithistide sp. collected from Seribu Island will be used for the host of associated microorganism. Agar medium used for isolation were M1 that contained amylum, yeast extract and peptone, M2 (10% marine broth media) contained yeast extract and peptone, M3 only sea water without adding any nutrients. Beside the nutrient variation, heat sock treatment at 50oC toward the sponge solution also apply to this study. The bacterial isolation data indicated that bacterial density in (CFU/100µL) of Theonella sp, Callispongia sp. and Lithistide sp. were minimum when spreading in M3 medium with heat sock treatment. This data showed that limiting in nutrient and heating could increasing bacterial selectivity. The antibacterial activity capability of bacterial strains isolated using M1, M2 and M3 respectively in range were 81,8-90,9%; 50-87,5% and; 66,7 -100%. This results showed that less nutrient of media will rise the number of antibacterial activity strains,and decreasing of bacterial density. This study reported that the minimum nutrient of isolation media and heat shock treatment could be used for selecting the antibacterial strains of sponge associated bacteria. Keywords : isolation media, antibacterial, nutrient, microbial symbiont AbstrakAktifitas farmakologi yang dihasilkan oleh mikroorganisme laut sangat dipengaruhi oleh nutrisi dan kondisi lingkungan. Hal tersebut mendorong untuk digali lebih dalam tentang aspek-aspek yang mempengaruhi seleksi mikroba potensial pada spons. Metode isolasi mikroba dari jaringan spons menjadi kunci dalam menguak potensi mikroba simbionnya. Dalam penelitian ini akan membahas pengaruh berbagai media isolasi bakteri yang berasosiasi dengan spons asal Kep. Seribu. Terhadap 3 specimen spons Theonella sp., Callispongia sp. dan Lithistide sp. dilakukan isolasi bakteri dengan metode direct sampling menggunakan media M1, M2 dan M3. Media M1 mengandung nutrisi antara lain amilum, ekstrak khamir dan pepton, sedangkan media M2 mengandung sumber nutrisi ekstrak khamir dan pepton dan M3 hanya media agar dan air laut. Selain variasi nutrient dalam media, perlakuan pemanasan pada suhu 50oC juga akan dilakukan terhadap larutan sampel spons sebelum dilakukan penyebaran pada media isolasi. Hasil isolasi bakteri yang diisolasi spons Theonella sp, Callispongia sp. dan Lithistide sp. menunjukkan bahwa kepadatan minimum diperoleh dengan menggunakan media M3 dengan perlakuan pemanansan. Dari data isolasi bakteri menunjukkan bahwa selain kandungan nutrient yang minimum, perlakuan pemanasan akan menurunkan kepadatan jumlah bakteri yang tumbuh, sehingga pemanasan merupakan salah satu cara dalam seleksi isolasi bakteri yang berasosiasi dengan spons. Hasil analisis aktivitas antibakteri menunjukkan bahwa persentase strain-strain bakteri yang aktif terhadap antimikroba Vibrio eltor, Eschericia coli dan Bacillus subtilis dengan variasi media M1 berkisar antara 81,8-90,9%; M2 berkisar 50-87,5% dan M3 berkisar 66,7-100%. Dari data tersebut disimpulkan bahwa semakin sedikitnya nutrisi media isolasi maka semakin tingginya mikroba-mikroba potensial penghasil antibiotik. Media M3 merupakan media yang selektif untuk isolasi mikroba potensial dari spons, terbukti dengan tingginya prosentase bakteri yang aktif dan berkurangnya jumlah koloni yang tumbuh.Kata kunci : media isolasi, antibakteri, nutrisi, mikroba simbion

Control of Endophytic Frankia Sporulation by Alnus Nodule Metabolites

A unique case of microbial symbiont capable of dormancy within its living host cells has been reported in actinorhizal symbioses. Some Frankia strains, named Sp+, are able to sporulate inside plant cells, contrarily to Sp− strains. The presence of metabolically slowed-down bacterial structures in host cells alters our understanding of symbiosis based on reciprocal benefits between both partners, and its impact on the symbiotic processes remains unknown. The present work reports a metabolomic study of Sp+ and Sp− nodules (from Alnus glutinosa), in order to highlight variabilities associated with in-planta sporulation. A total of 21 amino acids, 44 sugars and organic acids, and 213 secondary metabolites were detected using UV and mass spectrometric–based profiling. Little change was observed in primary metabolites, suggesting that in-planta sporulation would not strongly affect the primary functionalities of the symbiosis. One secondary metabolite (M27) was detected only in Sp+ nodules. It was identified as gentisic acid 5-O-β-d-xylopyranoside, previously reported as involved in plant defenses against microbial pathogens. This metabolite significantly increased Frankia in-vitro sporulation, unlike another metabolite significantly more abundant in Sp− nodules [M168 = (5R)-1,7-bis-(3,4-dihydroxyphenyl)-heptane-5-O-β-d-glucopyranoside]. All these results suggest that the plant could play an important role in the Frankia ability to sporulate in planta and allow us to discuss a possible sanction emitted by the host against less cooperative Sp+ symbionts.