SERGIO PAOLO BARAHONA PADILLA
@phd student
Escuela de Ciencias del Mar / Facultad de Ciencias del Mar y Geografía
Pontificia Universidad Católica de Valparaíso
EDUCATION
BSc. in Genetics and Biotechnology
MSC. Sea Sciences
PhD Student, Biotechnology
RESEARCH, TEACHING, or OTHER INTERESTS
Genetics, Molecular Biology, Biotechnology, General Biochemistry, Genetics and Molecular Biology
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
Manuel Beltrán, Juan Quimi Mujica, Benoit Diringer, and Sergio P. Barahona
Pontificia Universidad Catolica de Valparaiso
Acute hepatopancreatic necrosis disease (AHPND), attributed to the production of PirA/PirB toxins by certain Vibrio sp. strains, poses a significant threat to global shrimp aquaculture, causing substantial mortality and economic losses. To enhance our understanding of this disease within a closed culture system on the northern coast of Peru, we conducted a comparative analysis of the gut microbiomes between healthy and diseased postlarvae. Diseased postlarvae were obtained through exposure to an AHPND-causing strain of Vibrio parahaemolyticus. Five healthy and five diseased postlarvae were randomly sampled from experimental rearing tanks, and their medial guts were extracted. High-throughput sequencing targeting the V4 region of the 16S rRNA gene was employed for amplicon library construction, and assessments of alpha and beta diversities and taxonomic composition were conducted. Our results revealed reduced diversity and distinct compositional profiles in the gut microbiomes of diseased postlarvae. The order Rhodobacteriales was dominant in the gut microbiomes of healthy postlarvae. In contrast, the order Vibrionales (including an unassigned genus within Vibrionales, Vibrio, and Pseudoalteromonas) exhibited the highest abundance in diseased postlarvae. In conclusion, exposure to an AHPND-causing strain of V. parahaemolyticus induces significant dysbiosis in the gut microbiome of whiteleg shrimp postlarvae.
Alessandra Grández, André Ampuero, and Sergio P. Barahona
Pensoft Publishers
Nudibranchs, as a group, have received limited attention in terms of scientific study along the coastline of Peru. Here, an updated and comprehensive list of nudibranch species found in the Peruvian sea is presented, compiled through an extensive review of relevant literature. This compilation encompasses a total of 31 species, classified into two suborders, 10 superfamilies, 20 families, and 28 genera. With respect to the biogeographic provinces along the Peruvian coast, 23 species inhabit the Warm Temperate Southeastern Pacific province, 18 species occur in the Tropical Eastern Pacific province, and 10 species are found in both provinces, crossing the transitional zone between them. In terms of distribution patterns, two species exhibit a cosmopolitan distribution (Glaucus atlanticus and Fiona pinnata), while two species display a circumtropical distribution (Cephalopyge trematoides and Phylliroe bucephala). One species exhibits a bipolar distribution in the Eastern Pacific and possesses an amphi-South American distribution (Rostanga pulchra). Additionally, six species exhibit an amphi-South American distribution (Rostanga pulchra, Diaulula punctuolata, Doto uva, Tyrinna evelinae, Tyrinna delicata, and Doris fontainii), and two species are endemic to Peru (Corambe mancorensis and Felimare sechurana). This study provides comprehensive information on biogeographical aspects, geographical distributions, and taxonomic updates within the nudibranch species documented in Peru. Furthermore, we discuss the status of species listed in previous literature that have not been confirmed by collections, referring to them as potentially occurring species.
Ximena Velez‐Zuazo, Sergio P. Barahona, Omar G. Melo, Eric Hanschke, Ian Hanschke, and Monica C. Santa‐Maria
Wiley
AbstractThe Peruvian scallop (Argopecten purpuratus, Lamarck 1989) is a marine bivalve of high commercial value in the aquaculture industry, with wild populations distributing from northern Peru to Chile. Growing demand for it in the world aquaculture markets and limited availability of hatchery‐based seeds caused long‐term seed translocations among wild populations to recover depleted local populations and for production needs. We investigated long‐term translocation effects on the genetic diversity and structure of wild populations using next‐generation RAD sequencing. We sampled individuals from Sechura, Lobos de Tierra, Samanco, and Bahia Independencia in Peru, and La Rinconada in Northern Chile. We identified 8,345 polymorphic RAD loci and 24,218 SNPs for the five populations. We estimated high observed heterozygosity for all populations and high SNP frequency compared to similar studies on marine bivalves. We detected no spatial divergence among populations in Peru (pairwise FST from 0 to 0.003), but strong differentiation with the population in Chile. Migration rate estimates suggested asymmetric directionality of seed translocation. Overall, our results support a remnant effect of an intense historic translocation and ongoing gene flow among wild populations in Peru, challenging the identification of outlier loci and certification of sustainable origin of cultured scallops using genetic markers.
Diego Deville, Gustavo Sanchez, Sergio P. Barahona, Carmen Yamashiro, Daniel Oré-Chávez, Roger Quiroz Bazán, and Tetsuya Umino
Elsevier BV
Diego Deville, Gustavo Sanchez, Sergio Barahona, Carmen Yamashiro, Daniel Oré-Chávez, Roger Quiroz Bazán, and Tetsuya Umino
Springer Science and Business Media LLC
Sergio P. Barahona, Ximena Vélez‐Zuazo, Monica Santa‐Maria, and Aldo S. Pacheco
Wiley
AbstractBarriers to dispersal are recognized to play an important role in the differentiation of populations and ultimately in speciation. In the southeast Pacific, on the northern coast of Peru, a transition zone between the Peruvian and Panamic marine biogeographic provinces exists. Here, the convergence between two contrasting surface currents could generate a barrier effect for the larval dispersal of meroplanktonic invertebrates, which could in turn generate differentiated populations or genetic lineages on both sides of the transition zone. To address this, we studied to Echinolittorina paytensis, an abundant rocky intertidal periwinkle that spans both biogeographic provinces. A total of 95 individuals from Ecuador (2°19′S) to central Peru (7°31′S), covering the Panamic Province, the Peruvian Province, and the transition zone between, were collected. The mitochondrial markers cytochrome c oxidase I and 16SrRNA were sequenced in order to investigate phylogeography and genetic structuring. In general, no genetic structuring was found across the transition zone, suggesting this biogeographic boundary would not be acting as a barrier in this species. Factors such as a high larval dispersal capability and the occurrence of El Niño–Southern Oscillation events such as El Niño are discussed.
Sergio Paolo Barahona Padilla, Daniel Saúl Oré Chávez, and Roger Walter Quiroz Baza
Universidad Nacional Mayor de San Marcos, Vicerectorado de Investigacion
The Chub mackerel (Teleostei: Scombridae) supports an important fishery in the Southeastern Pacific, however, its population genetics status is currently unknown. In the present study the population genetic structure, gene flow and historical demography of this resource in the Northern Humboldt Current System were examined. Samples were collected between 2103 and 2014 from three fishing points off the Peruvian coast (Paita, Ventanilla and Ilo) and analyzed using mitochondrial D-Loop region sequences. A total of 29 polymorphic sites and 35 haplotypes were found in 72 individuals. Moderate haplotype diversity and very low levels of nucleotide diversity were found. Analysis of gene flow showed high levels of connectivity among sampling areas. Analysis of molecular variance, pairwise comparisons and genetic differentiation tests confirmed the lack of genetic structuring. These analyses suggest that analyzed sampling locations can be considered as a single gene pool. Migratory behavior, the high dispersal potential of early stages and the lack of oceanographic barriers can explain its genetic homogeneity along the Peruvian sea. The historical demography was also examined. Neutrality testing, mismatch distribution and Bayesian skyline plot suggested a population expansion scenario that took place during the Late Pleistocene. This study provides novel information about population genetics of the chub mackerel from the Southeastern Pacific.