Litoribacillus peritrichatus gen. nov. sp. nov., isolated from coastal sediment of an amphioxus breeding zone in Qingdao, China

Parathalassolituus penaei gen. nov., sp. nov., a novel member of the family Oceanospirillaceae isolated from a coastal shrimp pond in Guangxi, PR China

A Gram-stain-negative, strictly aerobic, rod-shaped and motile bacterium with bipolar flagella, designated G-43^T, was isolated from a surface seawater sample collected from an aquaculture in Guangxi, PR China. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain G-43^T was most closely related to the family Oceanospirillaceae and distantly to the most closely related genera Venatorbacter and Thalassolituus (95.52 % and 94.45-94.76 % 16S rRNA gene sequence similarity, respectively), while similarity values to other Oceanospirillaceae type strains were lower than 94.0 %. Strain G-43^T was found to grow at 4-30 °C (optimum, 25-28 °C), pH 6-9.0 (optimum, pH 7.0) and with 0-4.0 % NaCl (w/v; optimum at 2 % NaCl). Chemotaxonomic analysis of strain G-43^T indicated that the sole respiratory quinone was ubiquinone-8, the predominant cellular fatty acids were C_16 : 0, summed feature 3 (C_16 : 1 ω7c and/or C_16 : 1 ω6c) and summed feature 8 (C_18 : 1 ω7c and/or C_18 : 1 ω6c), and the major polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, aminolipid, diphosphatidylglycerol, phospholipids and an unidentified lipid. The G+C content of the genomic DNA was 55.4 mol%. The phylogenetic, genotypic, phenotypic and chemotaxonomic data demonstrate that strain G-43^T represents a novel species in a novel genus within the family Oceanospirillaceae, for which the name Parathalassolituus penaei gen. nov., sp. nov. is proposed. Strain G-43^T (=KCTC 72750^T= CCTCC AB 2022321^T) is the type and only strain of Parathalassolituus penaei.

Assessing the Effects of Rotifer Feed Enrichments on Turbot (Scophthalmus maximus) Larvae and Post-Larvae Gut-Associated Bacterial Communities

Live feed enrichments are often used in fish larvicultures as an optimized source of essential nutrients to improve larval growth and survival. In addition to this, they may also play an important role in structuring larval-associated microbial communities and may help improve their resistance to diseases. However, there is limited information available on how larval microbial communities and larviculture water are influenced by different live feed enrichments. In the present study, we investigated the effects of two commercial rotifer enrichments (ER) on turbot (Scophthalmus maximus) larval and post-larval gut-associated bacterial communities during larviculture production. We evaluated their effects on bacterial populations related to known pathogens and beneficial bacteria and their potential influence on the composition of bacterioplankton communities during larval rearing. High-throughput 16S rRNA gene sequencing was used to assess the effects of different rotifer enrichments (ER1 and ER2) on the structural diversity of bacterial communities of the whole turbot larvae 10 days after hatching (DAH), the post-larval gut 30 DAH, and the larviculture water. Our results showed that different rotifer feed enrichments were associated with significant differences in bacterial composition of turbot larvae 10 DAH, but not with the composition of larval gut communities 30 DAH or bacterioplankton communities 10 and 30 DAH. However, a more in-depth taxonomic analysis showed that there were significant differences in the abundance of Vibrionales in both 10 DAH larvae and in the 30 DAH post-larval gut fed different RE diets. Interestingly, the ER1 diet had a higher relative abundance of specific amplicon sequence variants (ASVs) related to potential Vibrio-antagonists belonging to the Roseobacter clade (e.g., Phaeobacter and Ruegeria at 10 DAH and Sulfitobacter at 30 DAH). In line with this, the diet was also associated with a lower relative abundance of Vibrio and a lower mortality. These results suggest that rotifer diets can affect colonization by Vibrio members in the guts of post-larval turbot. Overall, this study indicates that live feed enrichments can have modulatory effects on fish bacterial communities during the early stages of development, which includes the relative abundances of pathogenic and antagonist taxa in larviculture systems.

Litoribrevibacter albus gen. nov. sp. nov., isolated from coastal seawater, Fujian Province, China

A Gram-stain negative, short rod-shaped aerobic bacterium with flagella, designated strain Y32(T), was isolated from coastal seawater in Xiamen, Fujian Province of China. 16S rRNA gene sequence comparisons showed that strain Y32(T) is a member of the family Oceanospirillaceae, forming a distinct lineage with species of the genus Litoribacillus. The 16S rRNA gene sequence similarities between strain Y32(T) and other strains were all less than 94.0 %. Strain Y32(T) was found to grow optimally at 28 °C, at pH 7.0-8.0 and in the presence of 4-5 % (w/v) NaCl. The major fatty acids were identified as Summed Feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c, 49.4 %), C16:0 (17.7 %), C14:0 (6.9 %) and C18:1 ω9c (5.4 %). The major respiratory quinone was identified as ubiquinone-8 (Q-8). The major polar lipids were identified as diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol. The DNA G+C content of strain Y32(T) was determined to be 55.6 mol%. According to its morphology, physiology, fatty acid composition, polar lipids composition and 16S rRNA gene sequence data, strain Y32(T) represents a novel species of a new genus in the family Oceanospirillaceae, for which the name Litoribrevibacter albus gen. nov. sp. nov. is proposed. The type strain of Litoribrevibacter albus is Y32(T) (=MCCC 1F01211(T)=NBRC 110071(T)).

List of new names and new combinations previously effectively, but not validly, published

The purpose of this announcement is to effect the valid publication of the following effectively published new names and new combinations under the procedure described in the Bacteriological Code (1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should send three copies of the pertinent reprint or photocopies thereof, or an electronic copy of the published paper to the IJSEM Editorial Office for confirmation that all of the other requirements for valid publication have been met. It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries. It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in the nomenclature of prokaryotes. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.