Table S2. Details of the representative locations where MTB have been detected. Site Latitude Longitude Sample type Taxonomy of detected Reference(s) MTB South Atlantic 1726 -30.27 3.26 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1720 -29 13.83 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1719 -28.93 14.17 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1718 -28.7 15.21 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1717 -28.21 14.42 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1716 -27.96 14.01 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1712 -23.25 12.81 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1713 -23.22 13.13 Sediment Unknown Petermann and Bleil, 1993 *Itaipu Lagoon, Brazil -22.94977 -43.03406 Water and sediment Alphaproteobacteria Spring et al., 1998 Araruama Lagoon, Brazil -22.83333 -42.21667 Water and sediment Deltaproteobacteria Keim et al., 2004; Abreu et al., 2007 South Atlantic 1708 -20.1 8.97 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1707 -19.7 10.66 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1706 -19.56 11.18 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1705 -19.5 11.38 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1704 -19.41 11.61 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1703 -17.45 11.02 Sediment Unknown Petermann and Bleil, 1993 South Atlantic 1702 -6.57 10.32 Sediment Unknown Petermann and Bleil, 1993 Moreton Bay, Australia NA NA Sediment Unknown Taylor et al., 2001; Taylor and Barry, 2004 Tingalpa Creek, Australia NA NA Sediment Unknown Taylor et al., 2001 Irrigation ponds, Australia NA NA Sediment Unknown Taylor et al., 2001; Taylor and Barry, 2004 *Yunyue Lake, Hainan, China 19.49829 109.51485 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *HSL4, Mangrove swamp, Hainan, China 19.60287 110.79808 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 1 *HSL2, Mangrove swamp, Hainan, China 19.60299 110.79787 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *BMW1, Bamen Bay, Hainan, China 19.60472 110.8 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *BMW2, Bamen Bay, Hainan, China 19.61197 110.79465 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 YLS3, Yuelu Mountain, Changsha, Hunan, China 28.1671 112.93225 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *YLS1, Yuelu Mountain, Changsha, Hunan, China 28.17602 112.92961 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *YLS2, Yuelu Mountain, Changsha, Hunan, China 28.18264 112.93142 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *XJ1, Xiang River, Changsha, Hunan, China 28.20423 112.95373 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 and Nitrospirae and Deltaproteobacteria *XJ2, Xiang River, Changsha, Hunan, China 28.20463 112.9537 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 North Lake, China 30.6 114.51667 Sediment Alphaproteobacteria Li et al., 2007 Red-colored Pool at Edge of Salton Sea, California, USA 33.1954 -115.6148 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Alamo River near the Salton Sea, California, USA 33.1993 -115.5973 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a Lagoon at Salton Sea, California, USA 33.1997 -115.5886 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a *A pond in Catalina Island, CA, USA 33.4272 -118.4692 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *L1, Marine sediment from Catalina Island, CA, USA 33.42973 -118.50515 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *L2, Marine sediment from Catalina Island, CA, USA 33.43001 -118.50524 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 Zuma Beach, California, USA 34.0143 -118.821 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a *Qujiangchi in Xi'an, Shaanxi, China 34.21658 108.97968 Sediment Lin et al., 2012; Lin et al., 2013 Alphaproteobacteria and Deltaproteobacteria Kameno River, Wakayama prefecture, Japan NA NA Sediment Deltaproteobacteria Sakaguchi et al., 2002 *Moat in Xi'an, Shaanxi, China 34.25287 108.92187 Sediment Alphaproteobacteria, Lin et al., 2013; Wang et al., 2013 Deltaproteobacteria and 2 Gammaproteobacteria *Xingqing Lake in Xi'an, Shaanxi, China 34.25665 108.9793 Sediment Alphaproteobacteria, Lin et al., 2012; Lin et al., 2013 Deltaproteobacteria and Nitrospirae *Feng He Everglade, Xianyang, Shaanxi, China 34.32771 108.74424 Sediment Lake Tuendae, California, USA 35.1433 -116.1046 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Kururi, Chiba, Japan NA NA Sediment Arakaki et al., 2010 A freshwater pond in broadleaf woodland in Tokyo, Japan NA NA Water and sediment Alphaproteobacteria Thornhill et al., 1995 Koganei ponds, Japan 35.69947 139.50299 Water and sediment Alphaproteobacteria Kawaguchi et al., 1992; Burgess et al., 1993 Lake Mead, Nevada, USA 36.0461 -114.7965 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Boulder Beach, Lake Mead, Nevada, USA 36.0461 -114.7965 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a Badwater Basin in Death Valley National Park, California, USA 36.05 -116.63 Water and sediment Gammaproteobacteria Lefèvre et al., 2012b Huiquan Bay, China 120.34436 Water and sediment Alphaproteobacteria 36.05624 Alphaproteobacteria Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 Pan et al., 2008; Zhou et al., 2013 and Deltaproteobacteria Saddle Island, Lake Mead, Nevada, USA 36.0967 -114.8192 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a Callville Bay, Lake Mead, Nevada, USA 36.1411 -114.705 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a Boulder Beach, Lake Mead, Nevada, USA 36.045664 -114.795628 Water and sediment Nitrospirae Lefèvre et al., 2011b Blue Point Spring, Nevada, USA 36.389290 - 114.432961 Water and sediment Nitrospirae Lefèvre et al., 2011b Badwater Basin at Death Valley National Park, California, USA 36.2302 -116.7674 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Rogers Spring at Lake Mead, Nevada, USA 36.3774 -114.4438 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Spring at the Corn Creek Field Station, Nevada, USA 36.4389 -115.3589 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a Pond near Zion National Park, Utah, USA 37.2399 -113.1497 Water and sediment Alphaproteobacteria Lefèvre et al., 2011a; 2012a and Deltaproteobacteria Lake Yuehu, China 37.35 122.55 Sediment 3 Deltaproteobacteria Zhou et al., 2011 Kolob reservoir, Utah, USA 37.4334 -113.0432 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a *Intertidal zone, Weihai, Shandong, China 37.5317 122.04657 Sediment Lin et al., 2012; Lin et al., 2013 Pond near Mono Lake, California, USA 38.0444 -119.0764 Water and sediment Alphaproteobacteria Alphaproteobacteria Lefèvre et al., 2011a; 2012a and Deltaproteobacteria Bridgeport Reservoir, California, USA 38.318 -119.2133 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Pyramid Lake, Nevada, USA 39.845 -119.4405 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a *Lake Yuyuantan, Beijing, China 39.9152 116.30805 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *Lake Beihai, Beijing, China 39.92918 116.38393 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 and Nitrospirae Yuandadu park, Beijing, China 39.97436 116.37913 Sediment Alphaproteobacteria Lin and Pan, 2009 *Lake Kunming, Beijing, China 39.99487 116.27192 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 and Nitrospirae *YM3, Yuanmingyuan, Beijing, China 40.00617 116.29968 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *YM2, Yuanmingyuan, Beijing, China 40.00635 116.2974 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *YM1, Yuanmingyuan, Beijing, China 40.00895 116.29693 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 *Lake Miyun, Beijing, China 40.47012 116.92917 Sediment Alphaproteobacteria Lin et al., 2012; Lin et al., 2013 and Nitrospirae Great Boiling Springs, USA NA NA Water and sediment Nitrospirae Lefèvre et al., 2010 Great Boiling Springs Pool 4, Gerlach, Nevada, USA 40.6616 -119.3665 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Great Boiling Springs Pool 5, Gerlach, Nevada, USA 40.6619 -119.3664 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Great Boiling Springs Pool 6, Gerlach, Nevada, USA 40.6627 -119.3675 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Great Boiling Springs Pool 7, Gerlach, Nevada, USA 40.6651 -119.3628 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a *Salt Pond, Woods Hole, Massachusetts, USA 41.53333 -70.61667 Water Simmons et al., 2004; 2006 Alphaproteobacteria, Deltaproteobacteria and 4 Gammaproteobacteria Salt Pond, Woods Hole, Massachusetts, USA 41.5448 -70.627 Water and sediment Deltaproteobacteria Lefèvre et al., 2011a Pettasquamscutt estuary, USA NA NA Water and sediment Alphaproteobacteria Meldrum et al., 1993 Lake Ely, Pennsylvania, USA 41.7596 -75.8374 Water and sediment Alphaproteobacteria Lefèvre et al., 2012a McFarland pond, Ames, USA NA NA Water and sediment Alphaproteobacteria Schüler et al., 1999 Pointe Rouge, France 43.2406 5.37449 Water and sediment Alphaproteobacteria Lefèvre et al., 2009 *Lake Chiemsee, Germany 47.86667 12.48333 Water and sediment Alphaproteobacteria, Spring et al., 1992; 1993; Kolinko et al., 2012; 2013 Nitrospirae candidate and division OP3 Pond Martinsried, Germany NA NA Sediment Alphaproteobacteria Spring et al., 1994 A pool in Tubingen, Germany NA NA Sediment Alphaproteobacteria Spring et al., 1994 Stassfurt pond, Germany NA NA Water and sediment Alphaproteobacteria Flies et al., 2005 Bremen drainage ditch, Germany NA NA Water and sediment Alphaproteobacteria Flies et al., 2005 Wadden Sea, Germanu 53.89258 8.67608 Sediment Wenter et al., 2009; 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