<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Jennifer McGarry</dc:contributor>
  <dc:contributor>Maissa M Gaye</dc:contributor>
  <dc:contributor>Partha Basu</dc:contributor>
  <dc:contributor>Ronald S. Oremland</dc:contributor>
  <dc:contributor>John F. Stolz</dc:contributor>
  <dc:creator>Michael L. Wells</dc:creator>
  <dc:date>2019</dc:date>
  <dc:description>&lt;p id="p-4"&gt;The putative respiratory selenite [Se(IV)] reductase (Srr) from&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span id="named-content-3" class="named-content genus-species"&gt;Bacillus selenitireducens&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;MLS10 has been identified through a polyphasic approach involving genomics, proteomics, and enzymology. Nondenaturing gel assays were used to identify Srr in cell fractions, and the active band was shown to contain a single protein of 80 kDa. The protein was identified through liquid chromatography-tandem mass spectrometry (LC-MS/MS) as a homolog of the catalytic subunit of polysulfide reductase (PsrA). It was found to be encoded as part of an operon that contains six genes that we designated&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;srrE&lt;/i&gt;,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;srrA&lt;/i&gt;, s&lt;i&gt;rrB&lt;/i&gt;,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;srrC&lt;/i&gt;,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;srrD&lt;/i&gt;, and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;srrF&lt;/i&gt;. SrrA is the catalytic subunit (80 kDa), with a twin-arginine translocation (TAT) leader sequence indicative of a periplasmic protein and one putative 4Fe-4S binding site. SrrB is a small subunit (17 kDa) with four putative 4Fe-4S binding sites, SrrC (43 kDa) is an anchoring subunit, and SrrD (24 kDa) is a chaperon protein. Both SrrE (38 kDa) and SrrF (45 kDa) were annotated as rhodanese domain-containing proteins. Phylogenetic analysis revealed that SrrA belonged to the PsrA/PhsA clade but that it did not define a distinct subgroup, based on the putative homologs that were subsequently identified from other known selenite-respiring bacteria (e.g.,&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span id="named-content-4" class="named-content genus-species"&gt;Desulfurispirillum indicum&lt;/span&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;and&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;span id="named-content-5" class="named-content genus-species"&gt;Pyrobaculum aerophilum&lt;/span&gt;). The enzyme appeared to be specific for Se(IV), showing no activity with selenate, arsenate, or thiosulfate, with a&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;K&lt;sub&gt;m&lt;/sub&gt;&lt;/i&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;of 145 ± 53 μM, a&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;V&lt;/i&gt;&lt;sub&gt;max&lt;/sub&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;of 23 ± 2.5 μM min&lt;sup&gt;−1&lt;/sup&gt;, and a&lt;span&gt;&amp;nbsp;&lt;/span&gt;&lt;i&gt;k&lt;/i&gt;&lt;sub&gt;cat&lt;/sub&gt;&lt;span&gt;&amp;nbsp;&lt;/span&gt;of 23 ± 2.68 s&lt;sup&gt;−1&lt;/sup&gt;. These results further our understanding of the mechanisms of selenium biotransformation and its biogeochemical cycle.&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1128/JB.00614-18</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>American Chemical Society</dc:publisher>
  <dc:title>Respiratory selenite reductase from Bacillus selenitireducens strain MLS10</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>