INDUSTRIAL BIOTECHNOLOGY / Biofuels and Industrial Biotechnology
Development of biotechnological products and processes for agriculture and industry, microbial inoculants, biofertilizers and biocontrol agents; microbes and enzymes for improvement of bioenergy production processes
Description of Research
The Industrial Biotechnology Group focuses on the development of biotechnological products and processes to be used in agriculture and industry. The research projects currently in progress regard (i) the study of bacteria associated to crops such as soybean, maize, wheat and barley, focusing mainly on endophytic bacteria with clear beneficial properties in term of plant growth promotion through mechanisms such as N fixation, indolacetic acid production, phosphate solubilization and antagonism against microbial pathogens; (ii) the identification of plant cell wall degrading-bacteria and the heterologous expression of plant biomass degrading-enzymes to be used in processes of bioenergy production.
The interest towards endophytic bacteria is aimed at the development of inoculants suitable for use in the above mentioned crops to promote growth and to protect the plants from microbial pathogens. Bacterial endophytes are isolated from different crops, regions and agronomical conditions of Latin America and are further characterized to identify potential candidates/inoculants. This work is performed in collaboration with, and thanks to, the funds and infrastructures made available by companies in Italy and Argentina that are interested in developing and commercializing microbial inoculants. One of the plant associated bacteria that we have studied recently was also tested in field trials and showed promising results in term of plant growth promotion, increased biomass and yield (see Padukkage et al., 2021).
The second part of the project focuses on the improvement of processes for the generation of bioenergy from biomasses. Production of biogas is becoming an important process worldwide, as well as an opportunity to generate energy from waste. It consists in the conversion of biological waste to biogas, mainly methane, by means of consortia of methanogenic bacteria. One of the problems in this process is the low conversion rate due to the presence in waste of complex biopolymers or substrates that are poorly degraded. Therefore, pretreatment with microbial consortia or pool of enzymes particularly efficient in depolymerization of these molecoles could increase the production of biogas. Among the enzymes suitable for this application are those that degrade the plant cell wall, such as enzymes degrading cellulose (endoglucanases, cellobiohydrolases and b-glucosidases), hemicellulose (endoxylanases, b-xylosidases and related accessory enzymes), pectins (pectinases and polygalacturonases). We are currently developing heterologous expression systems, mainly E. coli and Pichia pastoris, to produce plant cell wall degrading enzymes for feedstock pretreatment before fermentation in anaerobic conditions and biogas production. Recently, a feedstock based on corn silage was pretreated with a bacterial endoglucanase expressed in E. coli and purified. Pretreated feedstock resulted in an increased yield of biomethane of more than 20% when the biochemical methane potential (BMP) was calculated over a period of 30 days (Degrassi et al., 2020).
Dimkic I, Bhardwaj V, Carpentieri-Pipolo V, Kuzmanovic N, Degrassi G (2021). The chitinolytic activity of the Curtobacterium sp. isolated from field-grown soybean and analysis of its genome sequence. PLoS ONE 16(11): e0259465.PLoS ONE link
Padukkage, D., Geekiyanage, S., Reparaz, J.M., Bezus R., Balatti P.A., Degrassi G. (2021). Bradyrhizobium japonicum, B. elkanii and B. diazoefficiens interact with rice (Oryza sativa), promote growth and increase yield. Curr Microbiol. 78:417-428. Springer link
Carpentieri-Pipolo V., Pereira Barreto T., Alves da Silva D., Vilela Abdelnoor R., Rockenbach Marin S., Degrassi G. (2021). Soybean improvement for lipoxygenase-free by simple sequence repeat (SSR) markers selection. J. Botanical Res. 3(1). DOI
Degrassi G., Hoshino R., Koijc M., Catone M., Vibha Bhardwaj V., and Rosato M.A. (2020). Increased biomethane production from endoglucanase-pretreated feedstock. J. Res. Environ. Sci. Toxicol. 9: 1-8. DOI
Degrassi G., Mortato V., Devescovi G., Hoshino R., Chatnaparat T., Kojic M., Carpentieri-Pipolo V., Zhao Y., Venturi V. (2019). Many plant pathogenic Pseudomonas savastanoi pv glycinea isolates possess an inactive quorum sensing ahlR gene via a point mutation. FEMS Microbiol Lett 366 DOI: 10.1093/femsle/fnz149 PubMed link
Carpentieri-Pipolo V., de Almeida Lopes K.B., Degrassi G. (2019). Phenotypic and genotypic characterization of endophytic bacteria associated with transgenic and non-transgenic soybean plants. Arch Microbiol 201(8):1029-1045. DOI: 10.1007/s00203-019-01672-6 PubMed link