Changes of the liver metabolome following an intravenous lipopolysaccharide injection in Holstein cows supplemented with dietary carnitine

Background:Carnitine facilitates the flux of long-chain fatty acids for hepatic mitochondrial beta-oxidation,which acts to ameliorate the negative energy balance commonly affecting high-yielding dairy cows.Inflammation triggered by lipopolysaccharide(LPS)load can however pose a challenge to the metabolic integrity via the expression of pro-inflammatory mediators,leading to immune system activation and respective metabolic alterations.The effect of enhanced carnitine availability on hepatic metabolome profiles during an inflammatory challenge has not yet been determined in dairy cows.Herein,Holstein cows were supplemented with 25 g/d rumen-protected carnitine from 42d prepartum until 126 d postpartum(n=16)or assigned to the control group with no supplementation during the same period(n=14).We biopsied the liver of the cows before(100 d postpartum)and after(112 d postpartum)an intravenous injection of 0.5μg/kg LPS.Liver samples were subjected to a targeted metabolomics analysis using the AbsoluteIDQ p180 Kit(Biocrates Life Sciences AG,Innsbruck,Austria).Results:Multivariate statistical analyses revealed that hepatic metabolome profiles changed in relation to both the carnitine supplementation and the LPS challenge.Comparing the metabolite profiles on 100 d,carnitine increased the concentration of short-and long-chain acyl-carnitines,which may be explained by an enhanced mitochondrial fatty acid shuttle and hence greater energy availability.The LPS injection affected hepatic metabolite profiles only in the carnitine supplemented group,particularly altering the concentration of biogenic amines.Conclusions:Our results point to interactions between an acute hepatic inflammatory response and biogenic amine metabolism,depending on energy availability.

Molecular mechanisms underlying the high mortality of hypervirulent Klebsiella pneumoniae and its effective therapy development

Dear Editor,Klebsiella pneumoniae(Kp)has become the most important bacterial pathogen causing high mortality rates in clinical patients due to the continuous evolution to several important variants such as carbapenem-resistant(CR-Kp),hypervirulent(hvKp)and both CR and hv K.pneumoniae(CR-hvKp).The high mortality caused by clinical hvKp is attributed to the non-response to antibiotic treatment.

Antibiotic Treatment Drives the Diversification of the Human Gut Resistome

Despite the documented antibiotic-induced disruption of the gut microbiota, the impact of antibiotic intake on strain-level dynamics, evolution of resistance genes, and factors influencing resistance dissemination potential remains poorly understood. To address this gap we analyzed public metagenomic datasets from 24 antibiotic treated subjects and controls, combined with an in-depth prospective functional study with two subjects investigating the bacterial community dynamics based on cultivation-dependent and independent methods. We observed that shortterm antibiotic treatment shifted and diversified the resistome composition, increased the average copy number of antibiotic resistance genes, and altered the dominant strain genotypes in an individual-specific manner. More than 30% of the resistance genes underwent strong differentiation at the single nucleotide level during antibiotic treatment. We found that the increased potential for horizontal gene transfer, due to antibiotic administration, was ～3-fold stronger in the differentiated resistance genes than the non-differentiated ones. This study highlights how antibiotic treatment has individualized impacts on the resistome and strain level composition, and drives the adaptive evolution of the gut microbiota.

Yak rumen microbiome elevates fiber degradation ability and alters rumen fermentation pattern to increase feed efficiency

Rumen microbes play an important role in ruminant energy supply and animal performance.Previous studies showed that yak(Bos grunniens)rumen microbiome and fermentation differ from other ruminants.However,little is understood about the features of the rumen microbiome that make yak adapted to their unique environmental and dietary conditions.This study was to investigate the rumen microbiome and metabolome to understand how yak adapt to the coarse forage and harsh environment in the Qinghai-Tibetan plateau.Nine female Qaidam yellow cattle(Bos taurus),9 dzomo(hybrids of cattle and yak)and 9 female plateau yak(B.grunniens),about 5 to 6 years old,were used in this study.Rumen fermentation parameters,fibrolytic enzyme activities,and rumen metataxonomic were determined.Then 18(6 samples per group)were selected for rumen metagenomic and metabolome analysis.Metataxonomic analysis revealed that the rumen microbiota was significantly different among plateau yak,Qaidam yellow cattle,and dzomo(P<0.05).Metagenomic analysis displayed a larger gene pool encoding a richer repertoire of carbohydrate-active enzymes in the rumen microbiome of plateau yak and dzomo than Qaidam yellow cattle(P<0.05).Some of the genes encoding glycoside hydrolases that mediate the digestion of cellulose and hemicellulose were significantly enriched in the rumen of plateau yak than Qaidam yellow cattle,but glycoside hydrolase 57 that primarily includes amylases was abundant in Qaidam yellow cattle(P<0.05).The rumen fermentation profile differed also,Qaidam yellow cattle having a higher molar proportion of acetate but a lower molar proportion of propionate than dzomo and plateau yak(P<0.05).Based on metabolomic analysis,rumen microbial metabolic pathways and metabolites were different.Differential metabolites are mainly amino acids,carboxylic acids,sugars,and bile acids.Changes in rumen microbial composition could explain the above results.The present study showed that the rumen microbiome of plateau yak helps its host to adapt to the Qinghai-Tibetan plateau.In particular,the plateau yak rumen microbiome has more enzymes genes involved in cellulase and hemicellulase than that of cattle,resulting higher fibrolytic enzyme activities inyak,further providing stronger fiber degradation function.

Short-wavelength light induces broiler’s behavioral and physiological syndrome through a misaligned eating rhythm

Previous work shows that long-wavelength light has a robust circadian rhythmic pattern in the expression of clock genes of chickens,whereas short-wavelength light leads to an arrhythmic oscillation of some clock genes(e.g.,cClock,cCry1,cCry2,cPer2,and cPer3).However,knowledge about the consequences of LED lights on the physiological and behavioral phenotype was still not clear.This experiment hypothesize that short-wavelength light disturbs chicken’s eating rhythm and leads to a wrong time to eat,resulting in metabolic syndrome.“Meihuang”broilers were housed in monochromatic LED blue light,green light,yellow light,red light,or white light with a very low dose(15 lx).Multiply physiological parameters were measured and the 24-h eating behavior was determined.The effects of LED light on physiological status and behavioral phenotype showed a wavelength-dependent manner.Short-wavelength light significantly decreased the level of total triglycerides and total cholesterol but increased triiodothyronine concentration.Inversely,long-wavelength light increased the triglycerides and total cholesterol and reduced the level of triiodothyronine.Further,it was found that short-wavelength light significantly boosted body weight compared with long-wavelength light,despite equivalent levels of food intake.Short-wavelength light induced 23.4%and 14.1%of food consumption during subjective nights,but long-wavelength light did not.These results imply that when chickens eat mattered,not just what they eat.Thus,low as 15 lx of blue light exposure during the typical dark period is sufficient to leads an individual to eat at“wrong”time,causing metabolic dysfunction.

Corrigendum to“Antibiotic Treatment Drives the Diversification of the Human Gut Resistome”[Genomics Proteomics Bioinformatics 17(1)(2019)39-51]

The editors regret there was an error in“Shotgun metagenome library construction and sequencing”section.“The raw sequences can be found in BGID(CRA000815)”should be corrected to“The raw metagenome sequencing data have been deposited in the Genome Sequence Archive at Beijing Institute of Genomics,Chinese Academy of Sciences(GSA:CRA000815),and are publicly accessible at https://bigd.big.ac.cn/gsa/”.The correct section is shown below.The editors would like to apologize for any inconvenience caused.

Surveillance of Multidrug-Resistant Bacterial Infections in Non-Adult Patients-Zhejiang Province,China,2014-2019

ABSTRACT Introduction:Antimicrobial resistance has become a major public health threat globally.The prevalence of multidrug-resistant(MDR)bacterial infections increased substantially among inpatients under 18 years of age in recent years.In Zhejiang Province,China,the trends of drug-resistance in non-adult patients from 2014 to 2019 were monitored,aiming to determine the variation patterns and epidemiological features of MDR strains.

Detection of a reassortant swine H1N2 influenza A virus from pigs in Hong Kong

Dear Editor,Influenza A viruses(IAVs)are responsible for significant respiratory illnesses in humans and a broad range of animal species.Repeated outbreaks and the rapid spread of genetically and antigenically distinct IAVs represent a considerable challenge for swine production.Pigs are susceptible to avian and human IAV infections and are considered“mixing vessels”where human,avian,and swine IAVs can recombine and generate novel reassortant influenza viruses with pandemic potential(Vincent et al.,2014).