Modern genomic tools can accelerate molecular breeding of underutilized crops such as teff (Eragrostis tef), a gluten-free cereal that is a staple in the Horn of Africa. Here, we report the development of a pangenome comprising chromosome-scale assemblies of 26 teff accessions, including both landraces and improved cultivars, and representing the species’ gene pool. The teff pangenome reveals a highly conserved genome architecture characterized by structural stability across different accessions, with a content of repetitive elements increased by 8% with respect to previous annotations. We describe the features of the pangenome and use it to advance teff biology, targeting seed color, a priority trait for breeding. By defining k-mer-based haplotypes at genomic loci previously known to be associated with the trait, we build a prediction model capable of accurately predicting the color of the seed. Our supervised classification analysis shows that seed color determination cannot be explained by less than four haplotype combinations at loci on chromosomes 4B and 6A. Our results represent a key resource to advance teff breeding and demonstrate that a pangenomic dimension can expand association studies to fully dissect the determination of complex traits.
The effect of past environmental changes on the demography and genetic diversity of natural populations remains a contentious issue and has rarely been investigated across multiple, phylogenetically distant species. Here, we perform comparative population genomic analyses and demographic inferences for seven widely distributed and ecologically contrasting European forest tree species based on concerted sampling of 164 populations across their natural ranges. For all seven species, the effective population size, Ne, increased or remained stable over many glacial cycles and up to 15 million years in the most extreme cases. Surprisingly, the drastic environmental changes associated with the Pleistocene glacial cycles have had little impact on the level of genetic diversity of dominant forest tree species, despite major shifts in their geographic ranges. Based on their trajectories of Ne over time, the seven tree species can be divided into three major groups, highlighting the importance of life history and range size in determining synchronous variation in genetic diversity over time. Altogether, our results indicate that forest trees have been able to retain their evolutionary potential over very long periods of time despite strong environmental changes. European forest tree species experienced strong climatic fluctuations over Quaternary. In spite of these pronounced environmental changes, population genomic analyses reveal that major forest tree species managed to retain their evolutionary potential over the period.
Mozambique does not have a tradition of farming Coffea arabica or Coffea canephora, the two species that dominate the worldwide coffee market. However, native coffee plants have been growing spontaneously and in some cases cultivated in the Ibo and Quirimba islands in the north of the country and Inhambane province in the south. Historically there has been confusion over the precise taxonomic classification of these indigenous coffee plants, with different botanists identifying the species as C. racemosa, C. zanguebariae or various synonyms of both. The present research aims to clarify the subject and provide new information on these little-described coffee species which may prove valuable as new breeding material for future cultivars, something that is sorely needed to face the present and future challenges of coffee production. Leaf samples were collected from 40 accessions from Ibo Island, Quirimba Island and Inhambane province. The samples were sequenced by whole-genome technology and WGS reads were filtered to identify relevant SNP variants. Diversity among the samples was assessed by PCA, and a phylogenetic tree including several Coffea species was built using additional data available in public databases. Experimental data confirm the presence of C. zanguebariae as the only coffee species present in both Ibo and Quirimba Islands, while it appears that C. racemosa is exclusive to the southern Inhambane province. The present research provides the most detailed analysis so far on the genetic identity of the traditional Mozambican coffee crops. This is the prerequisite for undertaking further scientific studies on these almost unknown coffee species and for starting agronomic development programs for the economic revival of Ibo and Quirimba islands based on coffee cultivation. Furthermore, these species could provide much-needed genetic material for the breeding of new hybrids with the two main commercial coffee species.
In order to better understand the mechanisms generating genetic diversity in the recent allotetraploid species Coffea arabica , here we present a chromosome-level assembly obtained with long read technology. Two genomic compartments with different structural and functional properties are identified in the two homoeologous genomes. The resequencing data from a large set of accessions reveals low intraspecific diversity in the center of origin of the species. Across a limited number of genomic regions, diversity increases in some cultivated genotypes to levels similar to those observed within one of the progenitor species, Coffea canephora , presumably as a consequence of introgressions deriving from the so-called Timor hybrid. It also reveals that, in addition to few, early-occurring exchanges between homoeologous chromosomes, there are numerous recent chromosomal aberrations including aneuploidies, deletions, duplications and exchanges. These events are still polymorphic in the germplasm and could represent a fundamental source of genetic variation in such a lowly variable species.
Delivering material selected for breeding purposes into the wild in the context of sustainable forest management might reduce the levels of genetic diversity of future forests in comparison to that of natural populations. Another consequence might be a reduction of their resilience under uncertain future climatic and socio-economic conditions if these new populations lack adaptability. Despite the long tradition of breeding activities in Europe, there is still a need to assess the impact of genetically enriched material on forests’ resilience. In this study, we address (1) the genetic diversity of selected material compared to its wild ancestors, and (2) how to enrich breeding material to support forests’ resilience under changing socio-environmental conditions. We analysed 16 study cases of selected material delivered from breeding activities in four European forest tree species (Pinus halepensis Mill., Pinus nigra J.F. Arnold, Pinus pinaster Ait. and Populus nigra L.) with different levels of breeding. To answer these two questions, we first assessed and compared the genetic diversity of selected material versus natural populations using both putatively neutral and adaptive (based on diverging selection) Single Nucleotide Polymorphisms (SNPs). We then suggest how to enrich these populations for resilience under future climatic conditions by defining a core collection for each species including material from populations that will likely disappear under future conditions. Thanks to the large SNP datasets available for our focal species, we were able to detect some trends in our data. Expected and observed heterozygosity values for selected populations were almost always identical. The selected material showed small but significant genetic differentiation from their original population and their inbreeding coefficient was generally lower. However, the level of genetic improvement (i.e. low vs high) was not correlated with the observed genetic differences between selected material and natural populations.The genetic characterization of natural populations distributed across the species range, and the future projection of their range stability, made it possible to identify core-collections that would significantly enrich breeding populations under uncertain future environmental conditions.
Huanglongbing (HLB), also known as citrus greening, represents the most devastating disease for citriculture, as it is causing the death of millions of trees, heavily decreasing the production and causing an annual economic loss of hundreds of million $. All the worldwide citriculture is threatened because all commercial citrus species and cultivars are susceptible to HLB. New curative and preventive measures are needed as well as identifying sources of durable and stable resistance to be used in breeding programs. Greening is associated to three species of Candidatus Liberibacter (CL), transmitted by two psyllids, Diaphorina citri and Trioza erytreae. Ca. L asiaticus (CLas) - D. citri is the most aggressive CL-vector combination. T. erytreae has been already detected in Portugal and Spain. Unfortunately, once the vector has spread widely, bacterial dispersal may occur rapidly. Therefore, one of the most ambitious challenges consists in the characterization and use of sources of resistance in Citrus relatives. Eremocitrus glauca and several Microcitrus species have been described as full-resistant to CLas but the resistance genes were not identified yet. Among Murraya spp., M. paniculata is a transient host for CLas, M. koenigii is full resistant, while the behaviour of M. ovatifoliolata is less clear. We present the de novo genome sequencing of E. glauca, M. paniculata and M. ovatifoliolata by using a combination of long-reads (Oxford Nanopore) and short-reads (Illumina) technologies. A genome of around 270 Mb was produced for E. glauca, 220 Mb for both Murraya species. Genomes were assembled in pseudomolecules; genes were predicted and annotated. These data will support further experiments aimed at identifying and characterizing genetic sources of resistance. They will be strategic for cisgenic or genomic editions approaches, to introduce the resistance in susceptible species, as well as to understand the inheritance of resistance in cross populations of E. glauca with Citrus species.
Climate change is one of the most important challenges for mankind in the far and near future. In this regard, sustainable production of woody crops on marginal land with low water availability is a major challenge to tackle. This dataset is part of an experiment, in which we exposed three genetically differentiated genotypes of Populus nigra originating from contrasting natural habitats to gradually increasing moderate drought. RNA sequencing was performed on fine roots, developing xylem and leaves of those three genotypes under control and moderate drought conditions in order to get a comprehensive dataset on the transcriptional changes at the whole plant level under water limiting conditions. This dataset has already provided insight in the transcriptional control of saccharification potential of the three Populus genotypes under drought conditions and we suggest that our data will be valuable for further in-depth analysis regarding candidate gene identification or, on a bigger scale, for meta-transcriptome analysis.
The genome of the allotetraploid species Coffea arabica L. was sequenced to assemble independently the two component subgenomes (putatively deriving from C. canephora and C. eugenioides) and to perform a genome-wide analysis of the genetic diversity in cultivated coffee germplasm and in wild populations growing in the center of origin of the species. We assembled a total length of 1.536 Gbp, 444 Mb and 527 Mb of which were assigned to the canephora and eugenioides subgenomes, respectively, and predicted 46,562 gene models, 21,254 and 22,888 of which were assigned to the canephora and to the eugeniodes subgenome, respectively. Through a genome-wide SNP genotyping of 736 C. arabica accessions, we analyzed the genetic diversity in the species and its relationship with geographic distribution and historical records. We observed a weak population structure due to low-frequency derived alleles and highly negative values of Taijma's D, suggesting a recent and severe bottleneck, most likely resulting from a single event of polyploidization, not only for the cultivated germplasm but also for the entire species. This conclusion is strongly supported by forward simulations of mutation accumulation. However, PCA revealed a cline of genetic diversity reflecting a west-to-east geographical distribution from the center of origin in East Africa to the Arabian Peninsula. The extremely low levels of variation observed in the species, as a consequence of the polyploidization event, make the exploitation of diversity within the species for breeding purposes less interesting than in most crop species and stress the need for introgression of new variability from the diploid progenitors.
Abstract Background We evaluated the functional capacity of plantaricin-producing Lactobacillus plantarum SF9C and S-layer-carrying Lactobacillus brevis SF9B to withstand gastrointestinal transit and to compete among the gut microbiota in vivo. Considering the probiotic potential of Lb. brevis SF9B, this study aims to investigate the antibacterial activity of Lb. plantarum SF9C and their potential for in vivo colonisation in rats, which could be the basis for the investigation of their synergistic functionality. Results A plantaricin-encoding cluster was identified in Lb. plantarum SF9C, a strain which efficiently inhibited the growth of Listeria monocytogenes ATCC® 19111™ and Staphylococcus aureus 3048. Homology-based three-dimensional (3D) structures of SF9C plantaricins PlnJK and PlnEF were predicted using SWISS-MODEL workspace and the helical wheel representations of the plantaricin peptide helices were generated by HELIQUEST. Contrary to the plantaricin-producing SF9C strain, the S-layer-carrying SF9B strain excluded Escherichia coli 3014 and Salmonella enterica serovar Typhimurium FP1 from the adhesion to Caco-2 cells. Finally, PCR-DGGE analysis of the V2–V3 regions of the 16S rRNA gene confirmed the transit of the two selected lactobacilli through the gastrointestinal tract (GIT). Microbiome profiling via the Illumina MiSeq platform revealed the prevalence of Lactobacillus spp. in the gut microbiota of the Lactobacillus-treated rats, even on the 10th day after the Lactobacillus application, compared to the microbiota of the healthy and AlCl3-exposed rats before Lactobacillus treatment. Conclusion The combined application of Lb. plantarum SF9C and Lb. brevis SF9B was able to influence the intestinal microbiota composition in rats, which was reflected in the increased abundance of Lactobacillus genus, but also in the altered abundances of other bacterial genera, either in the model of healthy or aberrant gut microbiota of rats. The antibacterial activity and capacity to withstand in GIT conditions contributed to the functional aspects of SF9C and SF9B strains that could be incorporated in the probiotic-containing functional foods with a possibility to positively modulate the gut microbiota composition.
A wild grape haplotype (Rpv3-1) confers resistance to Plasmopara viticola. We mapped the causal factor for resistance to an interval containing a TIR-NB-LRR (TNL) gene pair that originated 1.6-2.6 million years ago by a tandem segmental duplication. Transient coexpression of the TNL pair in Vitis vinifera leaves activated pathogen-induced necrosis and reduced sporulation compared with control leaves. Even though transcripts of the TNL pair from the wild haplotype appear to be partially subject to nonsense-mediated mRNA decay, mature mRNA levels in a homozygous resistant genotype were individually higher than the mRNA trace levels observed for the orthologous single-copy TNL in sensitive genotypes. Allelic expression imbalance in a resistant heterozygote confirmed that cis-acting regulatory variation promotes expression in the wild haplotype. The movement of transposable elements had a major impact on the generation of haplotype diversity, altering the DNA context around similar TNL coding sequences and the GC-content in their proximal 5 '-intergenic regions. The wild and domesticated haplotypes also diverged in conserved single-copy intergenic DNA, but the highest divergence was observed in intraspecific and not in interspecific comparisons. In this case, introgression breeding did not transgress the genetic boundaries of the domesticated species, because haplotypes present in modern varieties sometimes predate speciation events between wild and cultivated species.
The genetic control of self-incompatibility (SI) has been recently disclosed in olive. Inter-varietal crossing confirmed the presence of only two incompatibility groups (G1 and G2), suggesting a simple Mendelian inheritance of the trait. A double digest restriction associated DNA (ddRAD) sequencing of a biparental population segregating for incompatibility groups has been performed and high-density linkage maps were constructed in order to map the SI locus and identify gene candidates and linked markers. The progeny consisted of a full-sib family of 229 individuals derived from the cross ‘Leccino’ (G1) × ‘Dolce Agogia’ (G2) varieties, segregating 1:1 (G1:G2), in accordance with a diallelic self-incompatibility (DSI) model. A total of 16,743 single nucleotide polymorphisms was identified, 7,006 in the female parent ‘Leccino’ and 9,737 in the male parent ‘Dolce Agogia.’ Each parental map consisted of 23 linkage groups and showed an unusual large size (5,680 cM in ‘Leccino’ and 3,538 cM in ‘Dolce Agogia’). Recombination was decreased across all linkage groups in pollen mother cells of ‘Dolce Agogia,’ the parent with higher heterozygosity, compared to megaspore mother cells of ‘Leccino,’ in a context of a species that showed exceptionally high recombination rates. A subset of 109 adult plants was assigned to either incompatibility group by a stigma test and the diallelic self-incompatibility (DSI) locus was mapped to an interval of 5.4 cM on linkage group 18. This region spanned a size of approximately 300 Kb in the olive genome assembly. We developed a sequence-tagged site marker in the DSI locus and identified five haplotypes in 57 cultivars with known incompatibility group assignment. A combination of two single-nucleotide polymorphisms (SNPs) was sufficient to predict G1 or G2 phenotypes in olive cultivars, enabling early marker-assisted selection of compatible genotypes and allowing for a rapid screening of inter-compatibility among cultivars in order to guarantee effective fertilization and increase olive production. The construction of high-density linkage maps has led to the development of the first functional marker in olive and provided positional candidate genes in the SI locus.
Background: The influence of an S-layer-carrying strain Lactobacillus brevis SF9B and a plantaricin-producing strain Lactobacillus plantarum SF9C on the gut microbiota composition was evaluated in the rats. Considering the probiotic potential of Lb. brevis SF9B, this study aimed to examine the antibacterial activity of Lb. plantarum SF9C and potential for their in vivo colonisation , which could be the basis for the investigation of their synergistic functionality. Results: A plantaricin-encoding cluster was identified in Lb. plantarum SF9C, a strain which efficiently inhibited the growth of Listeria monocytogenes ATCC ® 19111™ and Staphylococcus aureus 3048. Contrary to the plantaricin-producing SF9C strain, the S-layer-carrying SF9B strain excluded Escherichia coli 3014 and Salmonella enterica serovar Typhimurium FP1 from adhesion to Caco-2 cells. Finally, DGGE analysis of the V2-V3 region of the 16S rRNA gene confirmed the transit of two selected lactobacilli through the gastrointestinal tract (GIT). Microbiome profiling via the Illumina MiSeq platform revealed the prevalence of Lactobacillus spp. in the gut microbiota of rats suggesting their colonisation potential in GIT. Conclusion: The combined application of Lb. plantarum SF9C and Lb. brevis SF9B could influence the intestinal microbiota composition, which is reflected through the increased abundance of Lactobacillus genus, but also through altered abundances of other bacterial genera, either in the model of healthy or aberrant microbiota of rats. The obtained results contributed to the functional aspects of SF9C and SF9B strains which could be incorporated in the probiotic-containing functional foods and therefore have a beneficial influence on the gut microbiota composition.
Background: The tetraploid durum wheat (Triticum turgidum L. ssp. durum Desf. Husnot) is an important crop which provides the raw material for pasta production and a valuable source of genetic diversity for breeding hexaploid wheat (Triticum aestivum L.). Future breeding efforts to enhance yield potential and climate resilience will increasingly rely on genomics-based approaches to identify and select beneficial alleles. A deeper characterisation of the molecular and functional diversity of the durum wheat transcriptome will be instrumental to more effectively harness its genetic diversity. Results: We report on the de novo transcriptome assembly of durum wheat cultivar 'Svevo'. The transcriptome of four tissues/organs (shoots and roots at the seedling stage, reproductive organs and developing grains) was assembled de novo, yielding 180,108 contigs, with a N50 length of 1121 bp and mean contig length of 883 bp. Alignment against the transcriptome of nine plant species identified 43% of transcripts with homology to at least one reference transcriptome. The functional annotation was completed by means of a combination of complementary software. The presence of differential expression between the A- and B-homoeolog copies of the durum wheat tetraploid genome was ascertained by phase reconstruction of polymorphic sites based on the T. urartu transcripts and inferring homoeolog-specific sequences. We observed greater expression divergence between A and B homoeologs in grains rather than in leaves and roots. The transcriptomes of 13 durum wheat cultivars spanning the breeding period from 1969 to 2005 were analysed for SNP diversity, leading to 95,358 non-rare, hemi-SNPs shared among two or more cultivars and 33,747 locus-specific (diploid inheritance) SNPs. Conclusions: Our study updates and expands the de novo transcriptome reference assembly available for durum wheat. Out of 180,108 assembled transcripts, 13,636 were specific to the Svevo cultivar as compared to the only other reference transcriptome available for durum, thus contributing to the identification of the tetraploid wheat pan-transcriptome. Additionally, the analysis of 13 historically relevant hallmark varieties produced a SNP dataset that could successfully validate the genotyping in tetraploid wheat and provide a valuable resource for genomics-assisted breeding of both tetraploid and hexaploid wheats.
BACKGROUND AND AIMS:The advent of molecular breeding is advocated to improve the productivity and sustainability of second-generation bioenergy crops. Advanced molecular breeding in bioenergy crops relies on the ability to massively sample the genetic diversity. Genotyping-by-sequencing has become a widely adopted method for cost-effective genotyping. It basically requires no initial investment for design as compared with array-based platforms which have been shown to offer very robust assays. The latter, however, has the drawback of being limited to analyse only the genetic diversity accounted during selection of a set of polymorphisms and design of the assay. In contrast, genotyping-by-sequencing with random sampling of genomic loci via restriction enzymes or random priming has been shown to be fast and convenient but lacks the ability to target specific regions of the genome and to maintain high reproducibility across laboratories.METHODS:Here we present a first adoption of single-primer enrichment technology (SPET) which provides a highly efficient and scalable system to obtain targeted sequence-based large genotyping data sets, bridging the gaps between array-based systems and traditional sequencing-based protocols. To fully explore SPET performance, we conducted a benchmark study in ten Zea mays lines and a large-scale study of a natural black poplar population of 540 individuals with the aim of discovering polymorphisms associated with biomass-related traits.KEY RESULTS:Our results showed the ability of this technology to provide dense genotype information on a customized panel of selected polymorphisms, while yielding hundreds of thousands of untargeted variable sites. This provided an ideal resource for association analysis of natural populations harbouring unexplored allelic diversities and structure such as in black poplar.CONCLUSION:The improvement of sequencing throughput and the development of efficient library preparation methods has made it feasible to carry out targeted genotyping-by-sequencing experiments cost-competitively with either random complexity reduction systems or traditional array-based platforms, while maintaining the key advantages of both technologies.
Sharka, a common disease among most stone fruit crops, is caused by the Plum Pox Virus (PPV). Resistant genotypes have been found in apricot (Prunus armeniaca L.), one of which—the cultivar ‘Lito’ heterozygous for the resistance—has been used to map a major quantitative trait locus (QTL) on linkage group 1, following a pseudo-test-cross mating design with 231 individuals. In addition, 19 SNP markers were selected from among the hundreds previously developed, which allowed the region to be limited to 236 kb on chromosome 1. A ‘Lito’ bacterial artificial chromosome (BAC) library was produced, screened with markers of the region, and positive BAC clones were sequenced. Resistant (R) and susceptible (S) haplotypes were assembled independently. To refine the assembly, the whole genome of ‘Lito’ was sequenced to high coverage (98×) using PacBio technology, enabling the development of a detailed assembly of the region that was able to predict and annotate the genes in the QTL region. The selected cultivar ‘Lito’ allowed not only to discriminate structural variants between the two haplotypic regions but also to distinguish specific allele expression, contributing towards mining the PPVres locus. In light of these findings, genes previously indicated (i.e., MATHd genes) to have a possible role in PPV resistance were further analyzed, and new candidates were discussed. Although the results are not conclusive, the accurate and independent assembly of R and S haplotypes of ‘Lito’ is a valuable resource to predict and test alternative transcription and regulation mechanisms underpinning PPV resistance.
Wood is a renewable resource that can be employed for the production of second generation biofuels by enzymatic saccharification and subsequent fermentation. Knowledge on how the saccharification potential is affected by genotype-related variation of wood traits and drought is scarce. Here, we used three Populus nigra L. genotypes from habitats differing in water availability to (i) investigate the relationships between wood anatomy, lignin content and saccharification and (ii) identify genes and co-expressed gene clusters related to genotype and drought-induced variation in wood traits and saccharification potential. The three poplar genotypes differed in wood anatomy, lignin content and saccharification potential. Drought resulted in reduced cambial activity, decreased vessel and fiber lumina, and increased the saccharification potential. The saccharification potential was unrelated to lignin content as well as to most wood anatomical traits. RNA sequencing of the developing xylem revealed that 1.5% of the analyzed genes were differentially expressed in response to drought, while 67% differed among the genotypes. Weighted gene correlation network analysis identified modules of co-expressed genes correlated with saccharification potential. These modules were enriched in gene ontology terms related to cell wall polysaccharide biosynthesis and modification and vesicle transport, but not to lignin biosynthesis. Among the most strongly saccharification-correlated genes, those with regulatory functions, especially kinases, were prominent. We further identified transcription factors whose transcript abundances differed among genotypes, and which were co-regulated with genes for biosynthesis and modifications of hemicelluloses and pectin. Overall, our study suggests that the regulation of pectin and hemicellulose metabolism is a promising target for improving wood quality of second generation bioenergy crops. The causal relationship of the identified genes and pathways with saccharification potential needs to be validated in further experiments.
Since 1985, CIRAD has been involved in surveying, collecting, studying and conserving ex situ wild cacao trees of French Guiana. Around 225 accessions of this genetic material (open progenies and clones), derived from 18 demes (sub-populations), are currently conserved in a collection at the Perennial Plants Biological Resource Centre (CRB-PPG) in French Guiana, at CIRAD's Paracou-Combi station, in Sinnamary. In 2004, an initial "core collection" of clones was founded on a virtually exhaustive representation of the different demes collected, with some phenotypically well-described clones. Following the genotyping of 181 of those clones by GBS (Genotyping by Sequencing), the availability of a large number of SNP markers (Single Nucleotide Polymorphism) enabled us to modernize the "core collection". Thus, of the 181 wild cacao trees clones, genotyped by 1953 SNPs (without missing data), a new core collection was obtained using COREFINDER software, comprising 41 clones representing 100% of the variability encountered.
17 S-layers represent the simplest biological membranes developed during the evolution and 18 are one of the most abundant biopolymers on Earth. Current fundamental and applied research 19 aim to reveal the chemical structure, morphogenesis and function of S-layer proteins (Slps). This is 20 the first paper that describes the Slps of certain Lactobacillus brevis strain isolated from sauerkraut. 21 The whole genome sequence (WGS) analysis of the L. brevis SF9B strain uncovered three genes 22 encoding the putative Slps, but merely one, identified as similar to the SlpB of L. brevis ATCC 14869, 23 was expressed. Slp-expressing SF9B cells exhibited increased survival in simulated gastrointestinal 24 M AN US CR IP T AC CE PT ED ACCEPTED MANUSCRIPT (GI) conditions and during freeze-drying. Their survival in stress conditions was additionally 25 enhanced by microencapsulation, especially when using alginate with gelatine as a matrix. Thus 26 prepared cells were subjected to simulated GI conditions and their mortality was only 0.28 ± 0.45 27 log CFU/mL. Furthermore, a correlation between the high surface hydrophobicity and the 28 remarkable aggregative capacity of SF9B strain was established. The results indicate a prominent 29 role of Slps in adhesion to mucin, extracellular matrix (ECM) proteins, and particularly to Caco-2 30 cells, where the removal of Slps utterly abolished the adhesiveness of SF9B cells for 7.78 ± 0.25 log 31 CFU/mL. 32