Mining Genomes of Three Marine Sponge-Associated Actinobacterial Isolates for Secondary Metabolism

Here, we report the draft genome sequences of three actinobacterial isolates, Micromonospora sp. RV43, Rubrobacter sp. RV113, and Nocardiopsis sp. RV163 that had previously been isolated from Mediterranean sponges. The draft genomes were analyzed for the presence of gene clusters indicative of secondary metabolism using antiSMASH 3.0 and NapDos pipelines. Our findings demonstrated the chemical richness of sponge-associated actinomycetes and the efficacy of genome mining in exploring the genomic potential of sponge-derived actinomycetes

Verzicht auf Anfütterung mit Kraftfutter vor der Abkalbung –Einfluss der Kraftfutterversorgung nach der Abkalbung auf den Vormagen pH-Wert von frischlaktierenden Milchkühen

The effects of two concentrate levels on reticuloruminal pH values of lactating cows were determined. An indwelling wireless data transmitting system for continuous pH measurement was given to 9 heifers and 11 cows orally 2 weeks before expected calving. All animals were fed with hay and grass silage, no concentrate was fed before parturition. After parturition cattle were assigned to one of two concentrate supplementation levels (Kon, Low). In group Kon the concentrate intake per cow increased from 2.5 kg DM in week 1 (17 % concentrate of DMI) to 7.2 kg in week 5 (38 % concentrate) and in group Low from 1.4 kg in week 1 (10 % concentrate of DMI) to 3.8 kg DM in week 5 (24 % concentrate). Before parturition no significant effects of week on daily mean pH was found but pH values varied between the animals. After parturition there were found no diet effects on daily mean pH and max. pH values (6.35 and 6.67, resp.). The min. pH differed significantly between Kon and Low but the absolute levels were almost equal (6.02 and 6.04, resp.). Although no transition feeding program before calving was performed the reticuloruminal pH values were not or only marginally affected by concentrate level at onset of lactation

Verzicht auf Anfütterung mit Kraftfutter vor der Abkalbung - Einfluss der Kraftfutterversorgung nach der Abkalbung auf den Vormagen pH-Wert von frischlaktierenden Milchkühen

In der vorliegenden Studie wurde der Einfluss von zwei Kraftfutterniveaus auf den Vormagen pH-Wert von Milchkühen, bei Verzicht auf Kraftfutteranfütterung vor der Abkalbung, untersucht. Dazu wurden 9 Kalbinnen und 11 Kühe zwei Wochen vor dem erwarteten Abkalbetermin Pansensensoren zur kontinuierlichen Messung des Vormagen pH-Wertes eingegeben. Alle Tiere wurden mit der Grundfutterbasis Heu und Grassilage gefüttert. Vor der Abkalbung wurde keine Kraftfutterfütterung durchgeführt. Nach der Abkalbung wurden die Tiere zwei Kraftfuttergruppen (Kon, Low) zugeteilt. In der hohen KF-Gruppe Kon stieg die Kraftfutteraufnahme von 2,5 kg TM (10 % KF i.d. Ration) in Laktationswoche 1 auf 7,2 kg TM (38 %) in Laktationswoche 5 an. In Low stieg diese von 1,4 (10 %) auf 3,8 kg TM (24 %) an. Vor der Abkalbung wurde kein signifikanter Wocheneffekt auf die Vormagen-pH-Werte festgestellt. Es zeigten sich jedoch bedeutende kuhindividuelle Unterschiede im pH-Wertniveau. Nach der Abkalbung wurde kein signifikanter Effekt des Kraftfutterniveaus (Kon, Low) auf den pH-Mittelwert (6,35) und das pH-Maximum (6,67) festgestellt. Das pH-Minimum unterschied sich zwar signifikant zwischen Kon und Low, die absoluten Werte lagen jedoch nahezu auf gleichem Niveau (6,02 und 6,04 für Kon und Low). Das pH-Wertniveau vor der Abkalbung beeinflusste signifikant die pH-Werte in den folgenden sechs Laktationswochen. Tiere welche mit niedrigerem pH-Wert zur Abkalbung kamen wiesen auch einen niedrigeren pH-Wert nach der Abkalbung auf und zeigten stärkere kurzfristige pH-Wert Schwankungen. Die vorliegenden Daten weisen darauf hin, dass bei wiederkäuergemäßer Rationsgestaltung und langsamer und begrenzter Kraftfuttersteigerung nach der Abkalbung aus pansenphysiologischer Sicht keine Anfütterung mit Kraftfutter vor der Abkalbung erforderlich ist. Die Ergebnisse unterstreichen die Bedeutung weiterer Forschungen zu kuhindividuellen pansenphysiologischen Unterschieden

Close relationship between pre- and post-calving reticuloruminal pH levels in dairy cows

The aim of the present study was to investigate the effects of the prepartum reticuloruminal pH values on the postpartum pH values of lactating cows at two concentrate supplementation levels. An indwelling pH measurement system with a wireless data transmitting unit was given to 9 heifers and 11 cows orally 2 weeks before expected calving. pH was measured from week 2 prepartum to week 6 postpartum. Prepartum, all animals were fed hay and grass silage only. After parturition the animals were assigned to one of two concentrate supplementation levels (Con and Low). During the first 6 weeks postpartum, 5.6 kg and 2.9 kg dry matter (DM) per day of concentrates were fed to cows in groups Con and Low, respectively. Before parturition, no effect of the week on the mean pH was found, but pH values varied considerably between individual animals. During the last week prior parturition, the median, lower and upper quartile values of the mean pH values were 6.47, 6.41 and 6.59 for heifers and 6.29, 6.19 and 6.39 for cows, respectively. Standard deviations of the mean pH values for heifers and cows were 0.15 and 0.12, respectively. After parturition, no diet effect on the mean pH and maximum pH values was found. The minimum pH differed between Con and Low, but the absolute levels were almost equal (6.02 and 6.04, resp.). A strong correlation (r> 0.8; P<0.01) between the mean pH value before parturition (pHweek-1) and pH values after parturition was found. Animals having lower pH levels before parturition continued to have lower mean pH and minimum pH values during weeks 1 to 6 postpartum. Furthermore, these animals had stronger short term fluctuations of H3O+ concentrations and a longer time span with pH values below 6.2. The results support the theory of the existence of cow-specific baselines concerning rumen pH, pointing to individual differences in the rumen environment, fermentation and metabolism and emphasising the importance of further research on this topic

Einfluss der Umstellung von Stall- auf Weidefütterung auf den Vormagen pH-Wert von Milchkühen

To investigate the effect of feed transition from barn feeding to pasture on the course of ruminal pH a study with 8 lactating dairy cows was undertaken. Therefore, an indwelling pH-measurement and data transmitting system was used. The experiment started at 27th March 2012 and a gradual transition from barn feeding to pasture feeding was done (periods P1-P6). After 7 days of barn feeding (P1) animals were given pasture progressively with increasing grazing time from 2 to 7 h/d (P2, day 8-14). In P3 (day 15-21) the cows spent 7 hours/d on pasture. Beginning on day 22, animals had 20 h/d access to pasture (continuous grazing), only semi-daily interrupted for 2 hours for milking and additional feeding (P4-P6). During the barn feeding period (P1), average ruminal pH was highest (6.44) and deviation of H+-ion concentration was lowest. In P2 and P3 ruminal pH depressed significantly (6.24 and 6.21 resp.) and increased again from P4 to P6 (6.30, 6.33, 6.36 resp.). The short-term deviation of H+-ion concentration was highest in the first week of day and night grazing (P4)

Draft genome of the Arabidopsis thaliana phyllosphere bacterium, Williamsia sp. ARP1

The Gram-positive actinomycete Williamsia sp. ARP1 was originally isolated from the Arabidopsis thaliana phyllosphere. Here we describe the general physiological features of this microorganism together with the draft genome sequence and annotation. The 4,745,080 bp long genome contains 4434 protein-coding genes and 70 RNA genes. To our knowledge, this is only the second reported genome from the genus Williamsia and the first sequenced strain from the phyllosphere. The presented genomic information is interpreted in the context of an adaptation to the phyllosphere habitat

Draft genome sequences of three chemically rich actinomycetes isolated from Mediterranean sponges

Metabolomic analysis has shown the chemical richness of the sponge-associated actinomycetes Streptomyces sp. SBT349, Nonomureae sp. SBT364, and Nocardiopsis sp. SBT366. The genomes of these actinomycetes were sequenced and the genomic potential for secondary metabolism was evaluated. Their draft genomes have sizes of 8.0, 10, and 5.8Mb having 687, 367, and 179 contigs with a GC content of 71.6, 70.7, and 72.7%, respectively. Moreover, antiSMASH 3.0 predicted 108, 149, and 75 secondary metabolite gene clusters, respectively which highlight the metabolic capacity of the three actinomycete species to produce diverse classes of natural product

Biodiversity, Anti-Trypanosomal Activity Screening, and Metabolomic Profiling of Actinomycetes Isolated from Mediterranean Sponges

Marine sponge–associated actinomycetes are considered as promising sources for the discovery of novel biologically active compounds. In the present study, a total of 64 actinomycetes were isolated from 12 different marine sponge species that had been collected offshore the islands of Milos and Crete, Greece, eastern Mediterranean. The isolates were affiliated to 23 genera representing 8 different suborders based on nearly full length 16S rRNA gene sequencing. Four putatively novel species belonging to genera Geodermatophilus, Microlunatus, Rhodococcus and Actinomycetospora were identified based on a 16S rRNA gene sequence similarity of < 98.5% to currently described strains. Eight actinomycete isolates showed bioactivities against Trypanosma brucei brucei TC221 with half maximal inhibitory concentration (IC50) values <20 μg/mL. Thirty four isolates from the Milos collection and 12 isolates from the Crete collection were subjected to metabolomic analysis using high resolution LC-MS and NMR for dereplication purposes. Two isolates belonging to the genera Streptomyces (SBT348) and Micromonospora (SBT687) were prioritized based on their distinct chemistry profiles as well as their anti-trypanosomal activities. These findings demonstrated the feasibility and efficacy of utilizing metabolomics tools to prioritize chemically unique strains from microorganism collections and further highlight sponges as rich source for novel and bioactive actinomycetes