How much does phytohormones affect thraustochytrid biomass?4 answersPhytohormones have been identified as significant enhancers of biomass and lipid productivity in various microalgae and protist species, including thraustochytrids, which are fungoid protists common in marine and estuarine habitats. The research by Kimura et al. provides a baseline understanding of thraustochytrid biomass in natural environments, highlighting their substantial presence and potential impact on microbial food chains and carbon cycling in coastal ecosystems. This foundational knowledge sets the stage for exploring the effects of phytohormones on thraustochytrid biomass enhancement.
Studies on microalgae have shown that phytohormones like indole-3-butyric acid and gibberellic acid can significantly increase biomass, lipids, and protein contents, suggesting a promising avenue for enhancing thraustochytrid biomass for applications such as biodiesel production. Guldhe et al. further support this by demonstrating that optimized concentrations of different phytohormones can lead to substantial increases in biomass productivity in Chlorella sorokiniana, a model microalga. Similarly, the combined effect of nitrogen depletion and phytohormone supplementation has been shown to enhance lipid accumulation and growth in Nannochloropsis oceanica, indicating that similar strategies could be effective for thraustochytrids.
Moreover, Sarinas et al. highlight thraustochytrids' capacity to adsorb oil, suggesting their potential utility in bioremediation and biomass production. The application of gibberellic acid in Isochrysis galbana cultures resulted in improved growth and metabolite biosynthesis, which could be analogous to thraustochytrid responses to phytohormones. Additionally, the study by Nazir et al. on Aurantiochytrium sp. SW1 demonstrates that phytohormones can significantly enhance growth and docosahexaenoic acid (DHA) production, further supporting the potential of phytohormones in optimizing thraustochytrid biomass for various applications.
While direct studies on thraustochytrids and phytohormones are not detailed in the provided contexts, the evidence from related microorganisms suggests that phytohormones could substantially affect thraustochytrid biomass, warranting further investigation into specific phytohormonal effects on thraustochytrids for enhanced biomass and lipid production.
How much PUFA and ARA content is obtained with thraustochytrids co-culture?4 answersThraustochytrids, a group of marine protists, have been extensively studied for their ability to produce polyunsaturated fatty acids (PUFAs), including arachidonic acid (ARA), due to their significant biotechnological potential. Co-culture techniques, involving the cultivation of thraustochytrids with other microorganisms, have shown promising results in enhancing PUFA production. Specifically, a study involving the co-culture of Aurantiochytrium sp. with lactic acid bacteria demonstrated a significant increase in PUFA content, with the Lentilactobacillus kefiri K6.10 strain yielding a PUFA content of 30.89 mg g^−1 biomass, which is three times higher than the control. This indicates the effectiveness of co-culture strategies in stimulating PUFA bioaccumulation.
In terms of ARA production, isolating and identifying native strains of thraustochytrids from different environments has been a focus to optimize ARA yields. For instance, the Ulkenia visurgenis strain Lng2 was identified as a potent producer of ARA, with productivity increasing by 92% at a high C/N ratio, demonstrating the influence of culture parameters on ARA content.
Moreover, the exploration of various substrates and culture conditions has further elucidated the potential of thraustochytrids in PUFA production. Studies have shown that different strains can efficiently utilize both pure and crude glycerol to produce significant amounts of omega-3 and omega-6 fatty acids, with specific strains showing a preference for certain substrates over others. Additionally, the use of low-cost renewable substrates like volatile fatty acids has been investigated, revealing that certain strains can achieve high cell dry weight and total lipid concentration, thereby suggesting a cost-effective method for PUFA production.
In conclusion, the co-culture of thraustochytrids with other microorganisms, alongside the optimization of culture parameters and substrates, has proven to be a viable approach for enhancing the production of PUFAs and ARA. These findings underscore the potential of thraustochytrids in the sustainable production of valuable fatty acids for various applications.
How different transcription regulates the phytohormone production during flood stress?5 answersTranscription factors play a crucial role in regulating phytohormone production during flood stress. Studies have shown that under flooding conditions, genes such as ARF, AREB/ABF, DREB, MYC/MYB, and NAC are involved in the transcriptional regulation of phytohormones like abscisic acid (ABA), gibberellins (GA), and ethylene. Specifically, ABA is considered a negative regulator of morphological development during flooding, while GA is involved in controlling shoot elongation and root formation. Additionally, RNA sequencing analyses have identified flood-stress response genes that are highly related to both ABA and GA responses in flood-tolerant plant species like Fokienia hodginsii, indicating the genetic mechanisms underlying flood-resistant phenotypes. These findings highlight the intricate transcriptional regulation of phytohormones in plants facing flood stress.
Do fungi produce gaseous hormones for growth like ehtylene?5 answersFungi, including endophytic fungi, are known to produce gaseous hormones like ethylene that play crucial roles in growth and development. Ethylene is identified as a common metabolic product of various fungi, indicating its significance in fungal biology. Research suggests that ethylene acts as an upstream signal for jasmonic acid (JA) and salicylic acid (SA) pathways, while also functioning as a downstream signal for hydrogen peroxide (H2O2) and nitric oxide (NO) pathways in fungi-induced sesquiterpenoids biosynthesis. Additionally, fungal VOCs, including ethylene, are recognized as important chemical signaling molecules that mediate various interactions in microbial communities and ecosystems. Overall, the production of gaseous hormones like ethylene by fungi showcases their ability to utilize signaling molecules for growth regulation and environmental adaptation.
What is the effect of phytohormones in lettuce?4 answersPhytohormones in lettuce have various effects on plant growth and development. The application of phytohormone-based biostimulants can control plant development, reduce negative environmental impacts, and improve resource usage efficiency. Different phytohormones, such as gibberellic acid and salicylic acid, have been found to have positive effects on lettuce productivity. Exogenous hormones, including ACC, GA, calcium chloride, and SNP, can promote the germination of lettuce seeds and improve the germination rate. Elevated root-zone CO2 levels can alter phytohormone concentrations in lettuce, with increased shoot jasmonic acid (JA) concentration observed under elevated CO2. The effects of phytohormones on lettuce growth and development are species-specific, as seen in the diverse phytohormone responses between lettuce and sweet pepper plants under elevated CO2. Phytohormone supplementation has been shown to protect lettuce plants from metal-induced stress by upregulating detoxification mechanisms and promoting antioxidative systems.
How do phytohormones and PGRs affect plant pathogen interaction?5 answersPhytohormones and plant growth regulators (PGRs) play a crucial role in plant-pathogen interactions. These signaling molecules are involved in regulating the defense responses of plants against pathogens. Salicylic acid is important for defense against biotrophic and early-stage hemibiotrophic pathogens, while jasmonic acid and ethylene are key players in defense against necrotrophic and later-stage hemibiotrophic pathogens. Other hormones such as auxins, cytokinins, abscisic acid, gibberellins, brassinosteroids, and strigolactones, as well as nitric oxide, also contribute to the regulation of trophic divergence in plant-pathogen interactions. Viruses have been found to manipulate phytohormone levels to enhance their replication and spread, disrupting the plant's normal developmental physiology. Pathogens, including fungi, have evolved strategies to manipulate and hijack phytohormone signaling pathways in plants, leading to susceptibility and disease. Fungal effectors and phytohormone mimics are used by pathogens to manipulate defense responses and innate immunity in plants.
