Screening of xylose utilizing and high lipid producing yeast strains as a potential candidate for industrial application

Linnea Qvirist RICARDO VAZQUEZ JUAREZ Thomas Andlid (2022)

"Background: Sustainable production of oil for food, feed, fuels and other lipid-based chemicals is essential to meet the demand of the increasing human population. Consequently, novel and sustainable resources such as lignocel- lulosic hydrolysates and processes involving these must be explored. In this paper we screened for naturally-occurring xylose utilizing oleaginous yeasts as cell factories for lipid production, since pentose sugar catabolism plays a major role in efcient utilization of lignocellulosic feedstocks. Glycerol utilization, which is also benefcial in yeast-based oil production as glycerol is a common by-product of biodiesel production, was investigated as well. Natural yeast isolates were studied for lipid accumulation on a variety of substrates, and the highest lipid accumulating strains were further investigated in shake fask cultivations and fermenter studies on xylose and hydrolysate. Results: By collecting leaves from exotic plants in greenhouses and selective cultivation on xylose, a high frequency of oleaginous yeasts was obtained (>40%). Diferent cultivation conditions lead to diferences in fatty acid contents and compositions, resulting in a set of strains that can be used to select candidate production strains for diferent purposes. In this study, the most prominent strains were identifed as Pseudozyma hubeiensis BOT-O and Rhodosporidium toruloides BOT-A2. The fatty acid levels per cell dry weight after cultivation in a nitrogen limited medium with either glucose, xylose or glycerol as carbon source, respectively, were 46.8, 43.2 and 38.9% for P. hubeiensis BOT-O, and 40.4, 27.3 and 42.1% for BOT-A2. Furthermore, BOT-A2 accumulated 45.1% fatty acids per cell dry weight in a natural plant hydrolysate, and P. hubeiensis BOT-O showed simultaneous glucose and xylose consumption with similar growth rates on both carbon sources. The fatty acid analysis demonstrated both long chain and poly-unsaturated fatty acids, depending on strain and medium. Conclusions: We found various natural yeast isolates with high lipid production capabilities and the ability to grow not only on glucose, but also xylose, glycerol and natural plant hydrolysate. R. toruloides BOT-A2 and P. hubeiensis BOT-O specifcally showed great potential as production strains with high levels of storage lipids and comparable growth to that on glucose on various other substrates, especially compared to currently used lipid production strains..."

Artículo

Microbial lipids, Oleaginous yeast, Lignocellulose, Pseudozyma hubeiensis, Rhodosporidium toruloides BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA MICROBIOLOGÍA

Draft Genome Sequence of Pediococcus pentosaceus Strain PP16CC, Isolated from Oyster Crassostrea corteziensis

JULIO ANTONIO HERNANDEZ GONZALEZ RICARDO VAZQUEZ JUAREZ Jose Manuel Vazquez-Guillen Carlos Rangel Dávalos MARIA CRISTINA RODRIGUEZ PADILLA MAURILIA ROJAS CONTRERAS (2022)

"Pediococcus pentosaceus strain PP16CC comes from the intestine of Crassostrea corteziensis. A 1.82-Mbp draft genome of this strain was assembled using A5-miseq from illumina reads, resulting in 4 contigs and 1,856 predicted protein coding genes. Additionally, 23 proteins belonging to various glycosyl hydrolase families and 6 prophage regions were identified."

Artículo

Genome Sequence, Pediococcus pentosaceus BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) GENÉTICA ANIMAL GENÉTICA ANIMAL

Gene expression in primary hemocyte culture of the Pacific white shrimp Penaeus vannamei infected with different white spot syndrome virus (WSSV) strains

Delia Patricia Parrilla Taylor REGINA ELIZONDO GONZALEZ Jesús Neftalí Gutiérrez Rivera SILVIA ALEJANDRA GARCIA GASCA NORBERTO VIBANCO PEREZ MA. DE JESUS DURAN AVELAR RICARDO VAZQUEZ JUAREZ (2022)

"Five previously analyzed white spot syndrome virus (WSSV) strains from northwest Mexico,differing in their genome architecture as well as in virulence, were selected (high virulence JP and LG strains;moderate virulence GVE and DIV strains; and low virulence LC10 strain) to evaluate pathogenesis response in vitro. Expression of phagocytosis-activating protein PAP, manganese superoxide dismutase MnSOD and peroxiredoxin PRX, and two genes of immediate-early expression (IE1 and WSSV304) were measured by qPCR in a primary hemocyte cell culture from Penaeus vannamei at 1, 3, 6, 12, and 24 h post-infection (hpi). PAP expression was significantly higher at 1 and 3 hpi, and JP and LC10 strains induced the highest expression. The response of MnSOD was high at 1 hpi, and a significant increase in PRX expression was detected at 3 hpi, probably due to the occurrence of an oxidative burst; expression levels of MnSOD and PRX were significantly higher at 1 and 3 hpi, respectively, induced by the LG strain (high virulence), suggesting an acute response. In general, expression of most immune-related - genes decreased after the initial hours of infection. Expression levels of IE1 and WSSV304 were exceptionally high at 1 hpi in almost all five WSSV analyzed strains,confirming their efficient mechanism for replication and viral fitness. The results of this study do not show an accurate link between the genome size and WSSV virulence of the strains, albeit the strain with the smallest genome showed the highest virulence. All strains induced an early immune response in heterogeneous ways."

Artículo

Penaeus vannamei, virulence, gene expression, viral fitness, viral pathogenesis, immune response BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA BIOLOGÍA ANIMAL (ZOOLOGÍA) PATOLOGÍA ANIMAL PATOLOGÍA ANIMAL

How a holobiome perspective could promote intensification, biosecurity and eco-efficiency in the shrimp aquaculture industry

Eric Daniel Gutiérrez Pérez RICARDO VAZQUEZ JUAREZ FRANCISCO JAVIER MAGALLON BARAJAS MIGUEL ANGEL MARTINEZ MERCADO GRISEL ALEJANDRA ESCOBAR ZEPEDA Paola Magallón Servín (2022)

"The aquaculture industry faces many challenges regarding the intensification of shrimp rearing systems. One of these challenges is the release of excessive amounts of nitrogen and phosphorus into coastal areas, causing disruption in nutrient cycling and microbial equilibrium, which are important for coastal productivity. Biosecurity within the shrimp rearing systems can also be compromised by disruption to the nutrient fluxes, and as consequence the microbiome of the system. In certain conditions, these changes could lead to the blooming of potentially pathogenic bacteria. These changes in the external microbiome of the system and the constant fluctuations of nutrients can affect the intestinal microbiome of shrimp, which is involved in the growth and development of the host, affecting nutrient absorption, regulating metabolic processes, synthesising vitamins, modulating the immune response and preventing growth of pathogenic bacteria. It has been suggested that specific changes in the intestinal microbiome of Litopenaeus vannamei may be an avenue through which to overcome some of the problems that this industry faces, in terms of health, growth and waste. Recent research, however, has focussed mainly on changes in the intestinal microbiome. Researchers have overlooked the relevance of other aspects of the system, such as the microbiome from the benthic biofilms; zooplankton, plankton and bacterioplankton; and other sources of microorganisms that can directly affect the microbial status of the intestinal and epiphytic communities, especially in rearing systems that are based on intensification and microbial maturation processes, such as a biofloc system. It is therefore necessary to place holobiome studies into context, including the ‘holobiome of the aquaculture system’ (microbiomes that make up the culture system and their interactions) and not only the intestinal microbiome. Thus, we describe factors that affect the shrimp microbiome, the methodology of study, from sampling to bioinformatic workflows, and introduce the concept of the ‘holobiome of the aquaculture system’ and how this enables us to promote the intensification, biosafety and eco-efficiency of shrimp farming. The holobiome perspective implies a greater investment of resources and time for research, but it will accelerate the development of technology that will benefit the development and sustainability of the aquaculture industry."

Artículo

litopenaeus vannamei, microbiome, intensification, biofloc, holobiome of aquaculture systems CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGRARIAS PRODUCCIÓN ANIMAL NUTRICIÓN NUTRICIÓN

Isolation and characterization of endophytic bacteria associated with roots of jojoba (Simmondsia chinensis (Link) Schneid)

RICARDO VAZQUEZ JUAREZ TANIA ZENTENO SAVIN ENRIQUE MORALES BOJORQUEZ Elvia Pérez Rosales Lilia Alcaráz Meléndez María Esther Puente Eduardo Quiroz Guzmán (2017)

"In this communication, the diversity and beneficial characteristics of endophytic bacteria have been studied in Simmondsia chinensis that has industrial importance because of the quality of its seed oil. Endophytes were isolated (N = 101) from roots of the jojoba plants collected, of which eight were identified by partial sequencing of the 16S rDNA gene. The isolated bacteria were Bacillus sp., Methylobacterium aminovorans, Oceanobacillus kimchi, Rhodococcus pyridinivorans and Streptomyces sp. All isolates had at least one positive feature, characterizing them as potential plant growth promoting bacteria. In this study, R. pyridinivorans and O. kimchi are reported as plant growth promoters."

Artículo

Endophytic bacteria, plant growth promoters, Simmondsia chinensis, seed oil BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA BACTERIOLOGÍA BACTERIOLOGÍA