# Parasedimentitalea psychrophila sp. nov., a psychrophilic bacterium isolated from deep-sea sediment

An-Qi Li, Chan Zhang, Deng-Hui Li, Xiao-Qing Qi, Liang Meng, Long-Fei Wu, Xue-Gong Li, Wei-Jia Zhang

► To cite this version:

An-Qi Li, Chan Zhang, Deng-Hui Li, Xiao-Qing Qi, Liang Meng, et al. Parasedimentitalea psychrophila sp. nov., a psychrophilic bacterium isolated from deep-sea sediment. International Journal of Systematic and Evolutionary Microbiology, 2023, 73 (9), 10.1099/ijsem.0.006046. hal-04398445

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Distributed under a Creative Commons Attribution 4.0 International License
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Parasedimentitalea psychrophila sp. nov., a psychrophilic
bacterium isolated from deep-sea sediment

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An-Qi Li¹,², Chan Zhang¹,#, Deng-Hui Li³,⁴, Xiao-Qing Qi¹,†, Liang Meng³,⁴, Long-Fei Wu⁵,
Xue-Gong Li¹,³*, Wei-Jia Zhang¹,³*

¹Laboratory of Deep-Sea Microbial Cell Biology, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan, China

²University of Chinese Academy of Sciences, Beijing, China

³Institution of Deep-sea Life Sciences, IDSSE-BGI, Sanya, Hainan, China

⁴BGI-Qingdao, BGI-Shenzhen, Qingdao, China

⁵Aix Marseille Univ, CNRS, LCB, IMM, IM2B, Marseille, France

#Current address: Guangdong VTR BioTech Co., Ltd., Zhuhai, Guangdong, China

†Current address: Hainan Research Academy of Environmental Sciences, Sanya, Hainan, China

Correspondence: Wei-Jia Zhang: wzhang@idsse.ac.cn; Xue-Gong Li: xuegongli@idsse.ac.cn

;

Keywords: *Parasedimentitalea psychrophila*; psychrophile; deep-sea;

New tara: Pseudomonadota and related organisms

Running title: *Parasedimentitalea psychrophila* sp. nov

The GenBank/EMBL/DDBJ accession number for the 16S rRNA sequence of strain QS115T is MK801282. The complete genome sequence of QS115T has been deposited at GenBank/ENA/DDBJ under the accession number CP127247 (Chromosome) and CP127248 - CP127250 (Plasmids).

Abstract

A novel bacterium strain QS115T was isolated from deep-sea sediment collected from the South China Sea at a depth of 1,151 m. BlastN analyses showed 98.21 % sequence identity between 16S rRNA gene sequences of QS115T and that of the most closely related strain *Parasedimentitalea marina* W43T. We sequenced strain QS115T genome and found it shared 82.39 % average nucleotide identity (ANI), 26.3 % digital DNA-DNA hybridization (dDDH), and 85.32 % average amino acid
identity (AAI) with the type strain of *P. marina* W43<sup>T</sup>. Cells of strain QS115<sup>T</sup> were Gram-stain-
negative, rod-shaped, and grew optimally at 10 °C, pH 7.5 and 2 % (w/v) NaCl. The principal fatty
acids were summed feature 8 (C<sub>18:1</sub> ω7c/ω6c), major respiratory quinone was ubiquinone-10 and
predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, glycophospholipid,
phosphatidylglycerol, and phosphatidylcholine. Polyphasic analyses of physiological, phenotypic
characteristics and genomic analyses suggested that strain QS115<sup>T</sup> represents a novel species of the
genus *Parasedimentitalea*, for which the name *Parasedimentitalea psychrophila* sp. nov. is proposed
(type strain QS115<sup>T</sup> = MCCC 1K04395<sup>T</sup> = JCM 34219<sup>T</sup>).

39 Introduction

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The deep-sea accounts for approximately 75 % volume of the ocean and comprises over 50 % of
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ocean prokaryotes(1). The deep-sea is an extreme habitat characterized with high hydrostatic pressure
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and low temperature in general. It is now well-known that high pressure and low temperature had
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similar impact on microbial cells. For example, they both reduce the fluidity of membrane and induce
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the synthesis of unsaturated fatty acids in deep-sea microbes(2-4). However, the study of microbial
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cold- and high-pressure adaptation mechanism has been carried out in limited number of strains, due
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to the difficulties of cultivation of deep-sea microorganisms.

The genus *Parasedimentitalea* was first described in 2019 (5). It belongs to the family *Rhodobacteraceae* and comprises a single species of *P. marina* (https://lpsn.dsmz.de/genus/parasedimentitalea). The type strain of *P. marina* W43<sup>T</sup> was isolated from deep-sea water of the New Britain Trench at a depth of 4,000 m. It is Gram-stain-negative and contains phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as dominant polar lipids. The predominant cellular fatty acids are summed feature 8. Strain W43<sup>T</sup> was psychrotolerant with optimal temperatures of 16 – 20 °C and abundant genomic features involved in cold adaptation have been identified in its genome(6). The novel candidate strain QS115<sup>T</sup> of the genus *Parasedimentitalea* described in this study was isolated from the deep-sea sediment at a depth of 1,151 m in the South China Sea. It was psychrophilic and is proposed to represent a new species with the name *Parasedimentitalea psychrophila* sp. nov.

58 Isolation and Ecology

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Sediment samples were collected using pushcore mounted on HOV "shen hai yong shi" at a depth of
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1,151 m from the South China Sea (19°16' 4.8" N, 114° 21' 1.08" E) in March 2018. Pushcore sample
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was sliced at 2 cm intervals on board. Surface sediment was suspended and diluted with filtered sea
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water. A 100 µl aliquot with different dilution (10⁻³, 10⁻⁴ and 10⁻⁵) was plated on Agar Medium
(24.4770 g NaCl, 3.9170 g Na₂SO₄, 0.0960 g KBr, 0.0403 g SrCl₂·6H₂O, 4.9810 g MgCl₂·6H₂O, 1.2558 g CaCl₂·2H₂O, 0.1920 g NaHCO₃, 0.0260 g H₃BO₃, 0.0039 g NaF, 0.0010 g FePO₄, 0.5 g peptone, 0.1 g yeast extract and 15 g Bacto agar in 1 L distilled water). The plates were incubated at 10 °C. Colonies that showed different morphologies were selected and purified by repeated streaking on the same medium. The purified strain QS115T was routinely conserved in Marine broth 2216 medium (MB; BD Difco) with 25 % (v/v) glycerol at -80 °C. The cultivation of strain QS115T for morphological and biochemical analyses was carried out on MB and MA medium, unless otherwise noted.

## 16S rRNA Gene Phylogeny

Strain QS115T was collected by centrifugation (12,000 rpm, 10 min) at the logarithmic phase, genomic DNA of QS115T was extracted using TIANamp Bacteria DNA Kit (TIANGEN Biotech Co., LTD). The 16S rRNA gene was amplified by PCR with the universal primers 27F (5'-AGTTTGATCATGGCTCAG-3') and 1492R (5'-GGYTACCTTGTTACGACTT-3'). The amplified 16S rRNA gene was sequenced by company (Beijing Ruibio Biotech Co., Ltd), and a nearly complete 16S rRNA gene sequence (1,346 bp) of strain QS115T was obtained and has been deposited in the Genbank database under the accession number MK801282. Sequence similarity was determined by Blast against the EzBioCloud database (http://www.ezbiocloud.net/) (7), and the result suggested that strain QS115T shared the highest similarity with *Parasedimentitalea marina* W43T (98.21 % of 16S rRNA sequence identity), followed by *Zongyanglinia marina* DSW4-44T (98.07 %). Phylogenetic trees were constructed with MEGA X (8) using maximum-likelihood(9), neighbor-joining (10) and maximum-parsimony (11) methods. The topologies of the phylogenetic trees were evaluated by bootstrap analyses based on 1,000 replications. As shown in **Figure 1**, strain QS115T robustly branched with *P. marina* W43T, and together they formed a cluster with *Z. marina* DSW4-44T and *Z. huanghaiensis* CY05T. The phylogenetic topologies of these closely related strains were also confirmed using maximum-likelihood and minimum-parsimony methods (**Figure S1 and S2**, Supporting Information).

## Genomic Features and Phylogenomic Analysis

The genome sequence was determined by BGI-Qingdao (Qingdao, China) using the BGISEQ-500 platform. More than 1.05 Gb clean data were generated to reach approximately 219-fold depth of coverage. The resulting complete genome of strain QS115T contained 5,005,898 bp with a G + C content of 57.71 %, consisted of a circular chromosome of 4,839,724 bp and three circular plasmids ranging from 16,332 bp to 91,805 bp in length. A total of 4,819 protein-coding genes, 83 tRNA genes and 21 rRNA genes were identified. The genome of strain QS115T was deposited at the Genbank
database under the accession number CP127247 for chromosome and CP127248 - CP127250 for plasmids.

A genome-based phylogenetic tree was reconstructed based on an up-to-date bacterial core gene set (UBCG) consisting of 120 single-copy core genes via GTDB-Tk (v 1.7.0) (12). The whole-genome-based phylogenetic tree showed that strain QS115T formed a distinct branch with *P. marina* W43T, and together with the branch of *Z. marina* DSW4-44T and *Z. huanghaiensis* CY05T (Figure 2). The genome-based similarity between strain QS115T and closely related species was evaluated by two indices at DNA level: average nucleotide identities (ANI) (13) and in silico digital DNA-DNA hybridization (dDDH) (14), and two indices at protein level: average amino acid identities (AAI) (15) and percent of conserved proteins (POPC) (16) (Table S1). The ANIb values between strain QS115T and *P. marina* W43T, *Z. marina* DSW4-44T and *Z. huanghaiensis* CY05T were 82.39 %, 77.62 % and 77.56 % identical, respectively. The in silico dDDH value was calculated by the Genome-to-Genome Distance Calculator 3.0. (17) [the recommended results from formula 2 (identities/high-scoring segment pairs length), http://ggdc.dsmz.de/ggdc.php], the results indicated that strain QS115T shared 26.3 %, 21.5 %, and 21.4 % DNA relatedness with *P. marina* W43T, *Z. marina* DSW4-44T and *Z. huanghaiensis* CY05T, respectively. The AAI percentages between strain QS115T and the reference strains were 85.32 %, 81.17 % and 80.93 % identical, respectively, and the POCP values between them ranged from 68.83 % to 70.70 %. The threshold values for bacterial species discrimination were 95-96 % for ANI(18), 70% for DDH(14), 65-95% for AAI(15), and 50-80 % for POCP(19).
Therefore, the genome-based similarity between strain QS115T and closely related species were below the threshold value for bacterial species discrimination with respect to all four indices analyzed, indicating a novel genomic species of the genus *Parasedimentitalea*.

## Morphological and Physiological Characteristics

Strain QS115T formed smooth, white colonies with regular edges on MA medium after 20 days' incubation at 10 °C. Phase-contrast microscopy (BX53 with a DP80 digital camera, Olympus) and transmission electron microscopy (JEM-1230, JEOL Ltd.) observation showed that QS115T cells were Gram-stain-negative and polar flagellated rods (Figure 3), with a size of 3.5 - 4.5 µm in length and 0.5 - 1.0 µm in width. The motility of the cells was determined using semi-solid agar and the puncture method. Cells of strain QS115T could diffuse on the semi-solid agar and grow along the puncture line, while strain W43T couldn't.

The optimal growth conditions of strain QS115T were analyzed in MB medium. The tolerance of temperature was tested at 4, 10, 15, 20, 25, 30, 37 and 50 °C. The pH range [pH 5.0 - 9.0 in 0.5 unit increments, were adjusted using 10 mM MES (pH 5.0 - 6.0), PIPES (pH 6.5 - 7.5) and HEPES (pH
8.0 - 9.0) buffers, respectively] and tolerance to NaCl (0, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 5.0, 6.0, 7.0 and 10.0 %, w/v) were determined as previously described (20). All experiments were carried out in triplicate unless stated otherwise. Growth was recorded by measuring optical density at 600 nm (OD<sub>600nm</sub>) using a UV-Vis spectrophotometer (Cary60, Agilent Technologies) as previously described(21). Growth rates were calculated as described by Li *et al* (22). Marine broth with the addition of 10 mM NaNO<sub>3</sub> was prepared in an anaerobic glove box for the evaluation of growth under anaerobic condition. The inoculated anaerobic medium was transferred into the Hungate tubes and placed at 10 °C for 30 days (23). No growth was observed for strain QS115<sup>T</sup> and any of the reference strains after 30 days' incubation under anaerobic condition with NaNO<sub>3</sub> as electron acceptor.

Growth of strain QS115<sup>T</sup> was observed at temperatures ranging from 4 °C to 20 °C, with an optimal growth temperature at 10 °C (Table 1 and Figure S3, Supporting Information). It was noted that all three reference strains analyzed were able to grow at 25 °C with an optimal growth temperature over 20 °C (Table 1). The difference suggested that the psychrophilic strain QS115<sup>T</sup> was better adapted to the low-temperature environment. The pH and NaCl range for growth of strain QS115<sup>T</sup> were pH 7.0 to 8.0 (optimum, pH 7.5) and 1.0 - 5.0 % NaCl (optimum, 2.0 %) (Table 1 and Figure S3). Compared to the reference strains, the strain QS115<sup>T</sup> has a lower tolerance to NaCl and preference for neutral pH.

Oxidase and catalase activity, and hydrolysis of hypoxanthine, L-tyrosine, starch, casein, xanthine, xylan and Tween 80 were tested on MA medium. Strain QS115<sup>T</sup> was negative for catalase and oxidase activities. It was capable of utilizing xylan, xanthine, and Tween 80, but failed for hydrolysis of hypoxanthine and L-tyrosine. However, the difference was the closely reference strain *P. marina* W43<sup>T</sup> cannot utilize xanthine, *Z. huanghaiensis* CY05<sup>T</sup> could not utilize any of the five substances mentioned above, *Z. marina* DSW4-44<sup>T</sup> could utilize them except xylan. Carbon utilization was tested on basal agar medium supplemented with yeast extract (23.60 g NaCl, 0.64 g KCl, 4.53 g MgCl<sub>2</sub>·6H<sub>2</sub>O, 5.94 g MgSO<sub>4</sub>·7H<sub>2</sub>O, 1.30 g CaCl<sub>2</sub>·2H<sub>2</sub>O, 0.20 g NaNO<sub>3</sub>, 0.20 g NH<sub>4</sub>Cl, 15 g Bacto agar, 0.05 g yeast extract, 1 L distilled water) containing 0.2 % carbon source (24, 25). Strain QS115<sup>T</sup> could utilize pyruvic acid as carbon source, but not betaine, lysine or proline, which differed it from *P. marina* W43<sup>T</sup>. Biolog assay suggested that L-malic acid, TWEEN 20, β-hydroxy-D, L butyric acid, sodium butyrate, propionic acid and acetic acid could be utilized by *P. marina* W43<sup>T</sup> but not strain QS115<sup>T</sup>. Biochemical tests were carried out using API 20NE and API ZYM strips (bioMérieux) according to the manufacturer's instructions. The strain QS115<sup>T</sup> differed from phylogenetically related taxa by nitrate reduction, denitrification, presence of arginine dihydrolase, urease, β-galactosidase and protease, and assimilation of D-glucose, sodium citrate and phenylacetic acid. The
morphological, physiological and biochemical characteristics of the strain QS115T and closely related species were presented in Table 1.

Chemotaxonomic Characteristics

Cells of strain QS115T and closely related species (*P. marina* W43T, *Z. huanghaiensis* CY05T and *Z. marina* DSW4-44T) grown to exponential phase were collected for the analysis of fatty acids. Fatty acids were prepared by Beijing Biogenro (Beijing Biogenro Biotechnology Co., LTD). Cellular fatty acids were identified and quantified by gas chromatograph (Agilent Technologies 56890N) with the standard Microbial Identification System (MIDI Calibration Mix 1). Similar to the most closely related species, the major fatty acids of strain QS115T were summed feature 8 (C<sub>18:1</sub> ω7c/ω6c), but with a relatively lower proportion (54.4% in strain QS115T versus 89.4% in strain W43T) (Table 2). Meanwhile, strain QS115T had a higher amount of C<sub>16:0</sub>, C<sub>10:0</sub> 3-OH, C<sub>16:0</sub> 2-OH, C<sub>16:1</sub> 2-OH and summed feature 3 (C<sub>16:1</sub> ω7c/ω6c).

Polar lipids were extracted from 100 mg of freeze-dried cellular material, separated by two-dimensional thin-layer chromatography (TLC) and then identified according to a previously described method (26). Diphasphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and glycophospholipid were detected in strain QS115T (Figure S4, Supporting Information). The composition of polar lipids in strain QS115T was similar to *P. marina* W43T except for glycophospholipid, which was not reported in this strain. By means of a high-performance liquid chromatography-mass spectrometry system (HPLC-MS, Agilent), the isoprenoid quinone was measured. The major respiratory quinone of strain QS115T was ubiquinone 10, which was in accordance with the properties of the family Rhodobacteraceae.

Description of *Parasedimentitalea psychrophila* sp. nov.

*Parasedimentitalea psychrophila* sp. nov. [psy.chro'phi.la. Gr. adj. psychros cold; N.L. adj. philus (from Gr. adj. philos) loving; N.L. fem. adj. psychrophila referring to loving low temperatures].

Cells are Gram-stain-negative, mobile, rod-shaped with approximately 0.5 - 1.0 µm in width and 3.5 - 4.5 µm in length, aerobic, and oxidase- and catalase-negative. Colonies are smooth with regular edges, and 0.5 - 1.0 mm in diameter after 20 day's culture on MA medium. Growth occurs at 4 - 20 °C (optimum 10 °C), from pH 7.0 - 8.0 (optimum pH 7.5), and in the presence of 1.0 - 5.0 % (w/v) NaCl (optimum 2.0 %). Positive for hydrolysis of xylan, xanthine and Tween 80. Negative for hydrolysis of hypoxanthine, L-tyrosine, casein, DNA, and starch. Strain QS115T can utilize pyruvic acid as the sole carbon source for growth, but not lysine, succinic acid, betaine, proline, and histidine.
In the test of API 20NE, strain QS115T cannot utilize D-glucose, L-arabinose, D-mannose, D-mannitol, N-acetyl-glucosamine, D-maltose, potassium gluconate, capric acid, adipic acid, malic acid, trisodium citrate, and phenylacetic acid. Positive for β-galactosidase, but negative for reduction of nitrate to nitrite, reduction of denitrification, indole production, D-glucose fermentation, arginine dihydrolase, urease, β-glucosidase or gelatin hydrolysis. In the test of API ZYM, strain QS115T is positive for alkaline phosphatase, esterase (C4), esterase lipase (C8), leucine arylamidase, and acid phosphatase; weak positive for lipase (C14), valine arylamidase, and naphtol-AS-BI-phosphohydrolase; negative for cystine arylamidase, trypsin, α-chymotrypsin α-galactosidase, β-galactosidase, β-glucuronidase, α-glucosidase, β-glucosidase, n-acetyl-β-glucosaminidase, α-mannosidase, and α-fucosidase. The major ubiquinone is ubiquinone 10. The major fatty acids are summed feature 8 (C<sub>18:1</sub>ω7c/ω6c). The predominant polar lipids are diphosphatidylglycerol, phosphatidylethanolamine, glycophospholipid, phosphatidylglycerol and phosphatidylcholine. The DNA G + C content of the type strain is 57.71 %.

The type strain, QS115<sup>T</sup> (= MCCC 1K04395<sup>T</sup>= JCM 34219<sup>T</sup>), was isolated from a deep-sea sediment sample (1,151 m) collected from the South China Sea (119°16′ 4.8" N, 114° 21′ 1.08" E). The GenBank accession numbers for the 16S rRNA gene and genome sequences of strain QS115<sup>T</sup> are MK801282 and CP127247- CP127250, respectively.

## 210 Author statements

### 211 1.1 Author contributions

A.-Q.L.: conceptualization, investigation, formal analysis, validation, visualization, writing-original draft preparation. C.Z.: conceptualization, investigation. D.-H.L.: formal analysis, visualization. X.-Q.Q.: investigation, project administration. L.M.: supervision. L.-F.W.: supervision. X.-G.L.: supervision, writing-review and editing. W.-J.Z.: conceptualization, writing-original draft preparation, writing-review and editing.

### 217 1.2 Conflicts of interest

The authors declare that there are no conflicts of interest.

### 219 1.3 Funding information

This research was funded by grants ZDKJ2021028 and ZDKJ2019011 from the Major Scientific and Technological Projects of Hainan Province, grants NSFC 42176121 and 42076127 from the National
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<figure><img src="image_2.png" /><figcaption>**Figure 1.** Neighbour-joining tree based on 16S rRNA gene sequences showing the phylogenetic relationship of QS115T and related taxa. Bootstrap values (expressed percentages of 1,000 replications) greater than 60 % are given at the nodes. Filled circles indicate nodes recovered reproducibly with maximum-likelihood and maximum-parsimony trees. The sequences of *Alteromonas marina* SW-47T was used as outgroup and GenBank accession numbers are given in parentheses. Bar, 0.020 substitutions per nucleotide position.</figcaption></figure>
<figure><img src="image_3.png" /><figcaption>**Figure 2.** Neighbour-joining tree based on genome sequences comparisons showing the phylogenetic relationship of QS115T and related taxa. Bootstrap values (expressed percentages of 1,000 replications) greater than 60 % are given at the nodes. The sequences of *Alteromonas marina* SW-47T was used as an outgroup number are given in parentheses. Bar, 0.1 substitutions per nucleotide position.</figcaption></figure>
<figure><img src="image_4.png" /><figcaption>**Figure 3.** Transmission-electron microscopy image of a cell of strain QS115<sup>T</sup>. Bar: 1 µm.</figcaption></figure>

<caption>**Table 1.** Differential characteristics of QS115<sup>T</sup> and type strains of closely related species.</caption>

Strains: 1, QS115<sup>T</sup>; 2, *Parasedimentitalea marina* W43<sup>T</sup>; 3, *Zongyanglinia huanghaiensis* CY05<sup>T</sup>; 4, *Zongyanglinia marina* DSW4-44<sup>T</sup>. All strains and species were analyzed under the same laboratory conditions unless otherwise stated. "+", positive; "W", weakly positive; "-", negative.

<table><thead><tr><th>Characteristic</th><th>1</th><th>2</th><th>3</th><th>4</th></tr></thead><tbody><tr><td>Motility</td><td>+</td><td>-<sup>a</sup></td><td>-<sup>b</sup></td><td>-<sup>c</sup></td></tr><tr><td colspan="5"><strong>Growth conditions</strong></td></tr><tr><td>Temperature Range (optimum, °C)</td><td>4-20 (10)</td><td>10-25 (20)</td><td>10-25 (20)</td><td>15-25 (25)</td></tr><tr><td>NaCl Range (optimum, w/v %)</td><td>1-5 (2)</td><td>1-4 (3)</td><td>1-5 (3)</td><td>2-4 (3)</td></tr><tr><td>pH Range (optimum)</td><td>7.0-8.0 (7.5)</td><td>6.0-7.5 (7.0)</td><td>6.5-8.0 (7.0)</td><td>6.0-8.5 (6.5)</td></tr><tr><td colspan="5"><strong>Carbon utilization:</strong></td></tr><tr><td>Betaine</td><td>-</td><td>+</td><td>W</td><td>-</td></tr><tr><td>Lysine</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Proline</td><td>-</td><td>+</td><td>+</td><td>-</td></tr></tbody></table>
<table><tbody><tr><td>Pyruvic Acid</td><td>+</td><td>-</td><td>-</td><td>+</td></tr><tr><td colspan="5"><strong>Macromolecule utilization:</strong></td></tr><tr><td>Hypoxanthine</td><td>-</td><td>-</td><td>-</td><td>+</td></tr><tr><td>L-tyrosine</td><td>-</td><td>-</td><td>-</td><td>+</td></tr><tr><td>Tween 80</td><td>+</td><td>+</td><td>-</td><td>+</td></tr><tr><td>Xanthine</td><td>+</td><td>-</td><td>-</td><td>+</td></tr><tr><td>Xylan</td><td>+</td><td>+</td><td>-</td><td>-</td></tr><tr><td colspan="5"><strong>Biolog GEIII:</strong></td></tr><tr><td>D-Trehalose</td><td>-</td><td>-</td><td>-</td><td>+</td></tr><tr><td>D-Cellobiose</td><td>-</td><td>-</td><td>-</td><td>+</td></tr><tr><td>Glycerol</td><td>-</td><td>-</td><td>-</td><td>+</td></tr><tr><td>L-Malic Acid</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>β-Hydroxy-D, L Butyric Acid</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Propionic Acid</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Acetic Acid</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Sodium Butyrate</td><td>-</td><td>+</td><td>+</td><td>-</td></tr><tr><td colspan="5"><strong>API 20NE:</strong></td></tr><tr><td>Denitrification</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Arginine Dihydrolase</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Urease</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>Gelatin Hydrolysis</td><td>-</td><td>+</td><td>-</td><td>-</td></tr><tr><td>β-Galactosidase</td><td>+</td><td>+</td><td>-</td><td>+</td></tr><tr><td>D-Glucose</td><td>-</td><td>-</td><td>+</td><td>-</td></tr><tr><td>Trisodium Citrate</td><td>-</td><td>-</td><td>+</td><td>-</td></tr><tr><td>Phenylacetic Acid</td><td>-</td><td>-</td><td>+</td><td>-</td></tr><tr><td><strong>G+C content (%)</strong></td><td>57.71</td><td>55.9<sup>a</sup></td><td>54.2<sup>b</sup></td><td>54.3<sup>c</sup></td></tr></tbody></table>
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Data from the following studies: a. Ding *et al.* (2020); b. Xu *et al.* (2021); c. Choi *et al.* (2019);

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<caption>**Table 2.** Fatty acid compositions (%) of strain QS115<sup>T</sup> and closely related species.</caption>

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Strains: 1, QS115<sup>T</sup>; 2, *Parasedimentitalea marina* W43<sup>T</sup>; 3, *Zongyanglinia huanghaiensis* CY05<sup>T</sup>; 4, *Zongyanglinia marina* DSW4-44<sup>T</sup>. All data from this study unless otherwise stated. “-”: no data available. Fatty acids that represented <1 % in all strains were omitted. TR, Traces (<1 %).

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<table><thead><tr><th>Fatty acid</th><th>1</th><th>2</th><th>3</th><th>4</th></tr></thead><tbody><tr><td><strong>Saturated fatty acids</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>C<sub>16:0</sub></td><td>1.5</td><td>1.2</td><td>1.3</td><td>2.9</td></tr><tr><td>C<sub>18:0</sub></td><td>-</td><td>TR</td><td>TR</td><td>1.5</td></tr><tr><td><strong>Unsaturated fatty acids</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>C<sub>18:1</sub> ω7c 11-methyl</td><td>-</td><td>-</td><td>-</td><td>1.3</td></tr><tr><td><strong>Hydroxy fatty acids</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>C<sub>10:0</sub> 3OH</td><td>6.5</td><td>3.5</td><td>3.0</td><td>5.3</td></tr><tr><td>C<sub>16:0</sub> 2OH</td><td>3.7</td><td>2.8</td><td>2.5</td><td>8.7</td></tr><tr><td>C<sub>16:1</sub> 2OH</td><td>2.3</td><td>1.3</td><td>TR</td><td>-</td></tr><tr><td>C<sub>18:1</sub> 2OH</td><td>TR</td><td>TR</td><td>TR</td><td>-</td></tr><tr><td><strong>Others</strong></td><td></td><td></td><td></td><td></td></tr><tr><td>Sum in feature 3</td><td>4.1</td><td>TR</td><td>TR</td><td>-</td></tr><tr><td>Sum in feature 8</td><td>54.4</td><td>89.4</td><td>91.0</td><td>65.3</td></tr></tbody></table>

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