Zophobihabitans entericus gen. nov., sp. nov., a new member of the family Orbaceae isolated from the gut of a superworm Zophobas morio

Gut bacteria of adult and larval Cotinis nitida Linnaeus (Coleoptera: Scarabaeidae) demonstrate community differences according to respective life stage and gut region

The close association between bacteria and insect hosts has played an indispensable role in insect diversity and ecology. Thus, continued characterization of such insect-associated-microbial communities is imperative, especially those of saprophagous scarab beetles. The bacterial community of the digestive tract of adults and larvae of the cetoniine scarab species Cotinis nitida is characterized according to life stage, gut structure, and sex via high-throughput 16S rRNA gene amplicon sequencing. Through permutational ANOVAs of the resulting sequences, bacterial communities of the digestive system are shown to differ significantly between adults and larvae in taxon richness, evenness and relatedness. Significant bacterial community-level differences are also observed between the midgut and hindgut in adult beetles, while no significant host-sex differences are observed. The partitioning between bacterial communities in the larval digestive system is shown through significant differences in two distinct hindgut regions, the ileum and the expanded paunch, but not between the midgut and ileum portion of the hindgut region. These data further corroborate the hypothesis of strong community partitioning in the gut of members of the Scarabaeoidea, suggest hypotheses of physiological-digestive association, and also demonstrate the presence of a seemingly unusual non-scarab-associated taxon. These findings contribute to a general portrait of scarabaeoid digestive tract bacterial communities while illuminating the microbiome of a common new world cetoniine of the Gymnetini-a tribe largely neglected in scarab and beetle microbiome and symbiosis literature.

Muricauda chongwuensis sp. nov., isolated from coastal seawater of China

In the course of screening for bacterial predators, a Gram-stain-negative, non-flagellated, gliding, long rod-shaped, and yellow-pigmented bacterium, designated strain HICW^T, was isolated from coastal seawater of China. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain HICW^T represented a member of the genus Muricauda and showed the highest sequence similarity to M. aquimarina JCM11811^T (98.8%) and M. ruestringensis DSM13258^T (98.1%). The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain HICW^T and M. aquimarina JCM11811^T were 79.2% and 34.1%, respectively. NaCl was required for growth. Optimum growth occurred at 25-30 °C, 2.0-3.0% (w/v) NaCl with pH 7.0. Strain HICW^T showed some similar characteristics to the nonobligate bacterial predators, and the cells can attach to the prey cells. Strain HICW^T contained MK-6 as the predominant respiratory quinone and had iso-C_15:0, iso-C_15:1 G, and iso-C_17:0 3-OH as the major cellular fatty acids. The polar lipids contained phosphatidylethanolamine (PE), three unidentified phospholipids (PL1-PL3), one unidentified amino lipids (AL), and three unidentified polar lipids (L1-L3). The genome size of strain HICW^T was approximately 3.8 Mbp, with a G + C content of 41.4%. Based on the polyphasic evidence, strain HICW^T is proposed as representing a new species of the genus Muricauda, for which the name Muricauda chongwuensis sp. nov. is proposed. The type strain is HICW^T (= JCM 33643 ^T = MCCC 1K03769^T).