tRNA genes clustered and arranged according to each identical group

HIT: 1 Group(s).
Download Sequence Representative sequence of each cluster
View ClustalW result
Sort by Identical group No. Sort by the number of tRNAs in the Identical group
Select
Sequence ID Genome ID
(or Accession No.)
Phylum/Class
(Sample source for ENV)
Species Start End Direction AA Anticodon Genome/Seq. Info. Decision
Identical group No.197494 (139 seq.)
>WENV009973 AACY020268294 Marine microbial communities from Global Ocean Sampling (GOS) 1076 998 - Asp GTC [ENA]
>W1711088304 LSYT01000010 Bacteroidota Flavobacterium chilense [LSYT] 165057 164981 - Asp GTC [ENA] ¡û
>W1711088305 LSYT01000010 Bacteroidota Flavobacterium chilense [LSYT] 164279 164203 - Asp GTC [ENA] ¡û
>W1711135441 LUYZ01000002 Bacteroidota Bacteroidales bacterium Bact_08 [LUYZ] 862 786 - Asp GTC [ENA] ¡û
>W1711135452 LUYZ01000077 Bacteroidota Bacteroidales bacterium Bact_08 [LUYZ] 3306 3382 + Asp GTC [ENA] ¡û
>W1711393479 MEOQ01000038 Bacteroidota Bacteroidetes bacterium GWF2_43_63 [MEOQ] 78140 78066 - Asp GTC [ENA] ¡û
>W1711393676 MEPG01000062 Bacteroidota Bacteroidetes bacterium RIFOXYA12_FULL_40_10 [MEPG] 5602 5526 - Asp GTC [ENA] ¡û
>W1711431884 MIKE01000011 Bacteroidota Flavobacterium tructae spartansii [MIKE] 402000 401924 - Asp GTC [ENA] ¡û
>W1711431885 MIKE01000011 Bacteroidota Flavobacterium tructae spartansii [MIKE] 401338 401262 - Asp GTC [ENA] ¡û
>W1711502432 MKSR01000029 Bacteroidota Dyadobacter sp. 50-39 [MKSR] 111447 111371 - Asp GTC [ENA] ¡û
>W1711502433 MKSR01000029 Bacteroidota Dyadobacter sp. 50-39 [MKSR] 111345 111271 - Asp GTC [ENA] ¡û
>W1711621510 MPDE01000003 Bacteroidota Bacteroidetes bacterium MedPE-SWsnd-G2 [MPDE] 170961 171037 + Asp GTC [ENA] ¡û
>W1711689196 MSDT01000002 Bacteroidota Mangrovimonas sp. DI 80 [MSDT] 1275229 1275305 + Asp GTC [ENA] ¡û
>W1711712597 MTCC01000002 Bacteroidota Flavobacterium psychrophilum [MTCC] 90767 90691 - Asp GTC [ENA] ¡û
>W1711713490 MTDD01000003 Bacteroidota Flavobacterium oreochromis columnare [MTDD] 20982 20906 - Asp GTC [ENA] ¡û
>W1711713542 MTDD01000062 Bacteroidota Flavobacterium oreochromis columnare [MTDD] 13091 13167 + Asp GTC [ENA] ¡û
>W1711743964 MUFW01000001 Bacteroidota Flavobacterium sp. LM4 [MUFW] 1978324 1978400 + Asp GTC [ENA] ¡û
>W1711743965 MUFW01000001 Bacteroidota Flavobacterium sp. LM4 [MUFW] 1978690 1978764 + Asp GTC [ENA] ¡û
>W1711966557 NCWQ01000056 Bacteroidota Flavobacterium sp. AJR [NCWQ] 24610 24686 + Asp GTC [ENA] ¡û
>W1711966558 NCWQ01000056 Bacteroidota Flavobacterium sp. AJR [NCWQ] 25439 25515 + Asp GTC [ENA] ¡û
>C171059686 CP017259 Bacteroidota Formosa sp. Hel3_A1_48 [CP017259] 516091 516015 - Asp GTC - ¡û
>C171059712 CP017260 Bacteroidota Formosa sp. Hel1_33_131 [CP017260] 2051666 2051742 + Asp GTC - ¡û
>W131176843 ARKJ01000013 Bacteroidota Flavobacterium rivuli DSM 21788 [ARKJ] 14185 14261 + Asp GTC [ENA] ¡û
>W131176855 ARKJ01000019 Bacteroidota Flavobacterium rivuli DSM 21788 [ARKJ] 20406 20332 - Asp GTC [ENA] ¡û
>WENV180042395 LQAE01013761 [LQAE] bioreactor metagenome; bioreactor_1 inoculated with Wadden Sea sediment; 1st replicate of a sulfate-reducing system that 211 285 + Asp GTC [ENA] ¢þ
>WENV180102744 OAOZ01009155 [OAOZ] marine metagenome; ENVO:00002010 623 549 - Asp GTC [ENA] ¢þ
>WENV180114536 OAPS01016658 [OAPS] marine metagenome; sea water 613 539 - Asp GTC [ENA] ¢þ
>WENV180296747 OBJA01002250 [OBJA] soil metagenome; sediment, water from around vicinity 10297 10371 + Asp GTC [ENA] ¢þ
>WENV180357494 OBNN01018238 [OBNN] marine metagenome; Coastal water 506 582 + Asp GTC [ENA] ¢þ
>WENV180366272 OBOD01001678 [OBOD] marine metagenome; ENVO:00002010 984 1058 + Asp GTC [ENA] ¢þ
>WENV180381789 OBOS01023435 [OBOS] marine metagenome; ENVO 00002150 279 203 - Asp GTC [ENA] ¢þ
>WENV180650394 OCSY01018440 [OCSY] marine metagenome; 30 L Plastic container 268 194 - Asp GTC [ENA] ¢þ
>WENV181226860 OFDN01000206 [OFDN] hot springs metagenome; Water 22096 22022 - Asp GTC [ENA] ¢þ
>WENV181312283 OFJB01070866 [OFJB] sludge metagenome; sludge 42 116 + Asp GTC [ENA] ¢þ
>WENV181384047 OFRH01010249 [OFRH] wastewater metagenome; Exp Tend NO 100WW 915 989 + Asp GTC [ENA] ¢þ
>WENV181391633 OFRT01031488 [OFRT] seawater metagenome; seawater 465 539 + Asp GTC [ENA] ¢þ
>WENV181835754 OGVI01016474 [OGVI] freshwater metagenome; freshwater 564 638 + Asp GTC [ENA] ¢þ
>WENV181857406 OGWO01004024 [OGWO] freshwater metagenome; freshwater 725 799 + Asp GTC [ENA] ¢þ
>WENV182545052 OJBL01007211 [OJBL] seawater metagenome; Sea water 340 266 - Asp GTC [ENA] ¢þ
>WENV182545762 OJBN01022521 [OJBN] seawater metagenome; Sea water 528 602 + Asp GTC [ENA] ¢þ
>WENV182548635 OJBW01011609 [OJBW] seawater metagenome; Sea water 335 409 + Asp GTC [ENA] ¢þ
>WENV182553217 OJCR01000579 [OJCR] seawater metagenome; Sea water 1396 1470 + Asp GTC [ENA] ¢þ
>WENV182555209 OJCY01011768 [OJCY] seawater metagenome; Sea water 122 48 - Asp GTC [ENA] ¢þ
>WENV182558346 OJDM01000227 [OJDM] seawater metagenome; Sea water 1285 1211 - Asp GTC [ENA] ¢þ
>WENV182561748 OJDX01001741 [OJDX] seawater metagenome; Sea water 1285 1211 - Asp GTC [ENA] ¢þ
>WENV182561952 OJDY01000285 [OJDY] seawater metagenome; Sea water 1646 1720 + Asp GTC [ENA] ¢þ
>WENV182562820 OJEA01004018 [OJEA] seawater metagenome; Sea water 147 73 - Asp GTC [ENA] ¢þ
>WENV182563102 OJEB01000196 [OJEB] seawater metagenome; Sea water 2637 2563 - Asp GTC [ENA] ¢þ
>WENV182564184 OJEE01000372 [OJEE] seawater metagenome; Sea water 1292 1366 + Asp GTC [ENA] ¢þ
>WENV182564467 OJEF01000333 [OJEF] seawater metagenome; Sea water 10934 10860 - Asp GTC [ENA] ¢þ
>WENV182569221 OJEY01002703 [OJEY] seawater metagenome; Sea water 393 319 - Asp GTC [ENA] ¢þ
>WENV182570950 OJFF01018404 [OJFF] seawater metagenome; Sea water 215 289 + Asp GTC [ENA] ¢þ
>WENV182571798 OJFK01012190 [OJFK] seawater metagenome; Sea water 988 914 - Asp GTC [ENA] ¢þ
>WENV182576154 OJFX01004071 [OJFX] seawater metagenome; Sea water 3009 2935 - Asp GTC [ENA] ¢þ
>WENV182576608 OJFY01000490 [OJFY] seawater metagenome; Sea water 5127 5201 + Asp GTC [ENA] ¢þ
>WENV182578012 OJGM01000506 [OJGM] seawater metagenome; Sea water 4797 4871 + Asp GTC [ENA] ¢þ
>WENV182581497 OJGX01009777 [OJGX] seawater metagenome; Sea water 1263 1189 - Asp GTC [ENA] ¢þ
>WENV182582187 OJHA01000641 [OJHA] seawater metagenome; Sea water 1449 1523 + Asp GTC [ENA] ¢þ
>WENV182582552 OJHB01001278 [OJHB] seawater metagenome; Sea water 1928 2002 + Asp GTC [ENA] ¢þ
>WENV182588444 OJHT01003156 [OJHT] seawater metagenome; Sea water 570 644 + Asp GTC [ENA] ¢þ
>WENV182592755 OJIR01018668 [OJIR] seawater metagenome; Sea water 644 718 + Asp GTC [ENA] ¢þ
>WENV182594162 OJIV01000958 [OJIV] seawater metagenome; Sea water 7346 7420 + Asp GTC [ENA] ¢þ
>WENV183054762 OLGU01002782 [OLGU] seawater metagenome; Sea water 1195 1121 - Asp GTC [ENA] ¢þ
>WENV183061241 OLHZ01001738 [OLHZ] seawater metagenome; Sea water 4019 4093 + Asp GTC [ENA] ¢þ
>WENV183625213 OOGF01004403 [OOGF] marine metagenome; seawater 541 615 + Asp GTC [ENA] ¢þ
>WENV183720021 PDWJ01025017 [PDWJ] oral metagenome; swab sample of gingival sulcus (mouth) from 5 year old male Dolphin_J 309 235 - Asp GTC [ENA] ¢þ
>WENV170149127 CEOC01003693 [CEOC] marine metagenome genome assembly TARA_036_DCM_0.22-1.6 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 1140 1216 + Asp GTC [ENA] ¢þ
>WENV170228760 CEQG01038458 [CEQG] marine metagenome genome assembly TARA_076_MES_0.45-0.8 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 50002 50078 + Asp GTC [ENA] ¢þ
>WENV170232151 CEQI01029240 [CEQI] marine metagenome genome assembly TARA_076_SRF_0.45-0.8 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 193 117 - Asp GTC [ENA] ¢þ
>WENV170248594 CEQQ01142746 [CEQQ] marine metagenome genome assembly TARA_076_DCM_0.45-0.8 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 530 454 - Asp GTC [ENA] ¢þ
>WENV170274334 CERM01010788 [CERM] marine metagenome genome assembly TARA_067_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 364 288 - Asp GTC [ENA] ¢þ
>WENV170275220 CERM01074425 [CERM] marine metagenome genome assembly TARA_067_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 448 524 + Asp GTC [ENA] ¢þ
>WENV170285937 CERW01036743 [CERW] marine metagenome genome assembly TARA_066_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 1531 1455 - Asp GTC [ENA] ¢þ
>WENV170291533 CESA01139217 [CESA] marine metagenome genome assembly TARA_078_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 410 486 + Asp GTC [ENA] ¢þ
>WENV170298478 CESF01125266 [CESF] marine metagenome genome assembly TARA_093_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 350 424 + Asp GTC [ENA] ¢þ
>WENV170301187 CESH01010733 [CESH] marine metagenome genome assembly TARA_094_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 1789 1865 + Asp GTC [ENA] ¢þ
>WENV170301757 CESH01066788 [CESH] marine metagenome genome assembly TARA_094_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 484 410 - Asp GTC [ENA] ¢þ
>WENV170316351 CESP01034173 [CESP] marine metagenome genome assembly TARA_099_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 202 126 - Asp GTC [ENA] ¢þ
>WENV170317454 CESP01157945 [CESP] marine metagenome genome assembly TARA_099_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 423 499 + Asp GTC [ENA] ¢þ
>WENV170326413 CESU01000371 [CESU] marine metagenome genome assembly TARA_082_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 177 101 - Asp GTC [ENA] ¢þ
>WENV170326420 CESU01000695 [CESU] marine metagenome genome assembly TARA_082_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 21532 21456 - Asp GTC [ENA] ¢þ
>WENV170407085 CEUH01093900 [CEUH] marine metagenome genome assembly TARA_137_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 3808 3882 + Asp GTC [ENA] ¢þ
>WENV170489014 CEVP01036977 [CEVP] marine metagenome genome assembly TARA_150_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 3462 3386 - Asp GTC [ENA] ¢þ
>WENV170499055 CEVT01107640 [CEVT] marine metagenome genome assembly TARA_150_DCM_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 4016 3940 - Asp GTC [ENA] ¢þ
>WENV170522135 CEWG01071282 [CEWG] marine metagenome genome assembly TARA_102_SRF_0.22-3 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 5715 5791 + Asp GTC [ENA] ¢þ
>WENV170536352 CEWP01170676 [CEWP] marine metagenome genome assembly TARA_067_SRF_0.45-0.8 ,contig; saline water (ENVO:00002010), including plankton (ENVO:xxxxxxxx) 10016 9940 - Asp GTC [ENA] ¢þ
>WENV170559580 CXWL01130678 [CXWL] groundwater metagenome; biofilm material 5804 5880 + Asp GTC [ENA] ¢þ
>WENV170605276 FUWD010465124 [FUWD] metagenome; unknown 412 338 - Asp GTC [ENA] ¢þ
>WENV170606248 FUWD010636346 [FUWD] metagenome; unknown 381 305 - Asp GTC [ENA] ¢þ
>WENV170642634 JFJP01042640 [JFJP] microbial mat metagenome; purple microbial (photo- and chemosynthetic) mats found in low-oxygen high-sulfur sink 4961 5037 + Asp GTC [ENA] ¢þ
>WENV170642635 JFJP01042640 [JFJP] microbial mat metagenome; purple microbial (photo- and chemosynthetic) mats found in low-oxygen high-sulfur sink 5125 5201 + Asp GTC [ENA] ¢þ
>WENV170709010 LNFM01000068 [LNFM] activated carbon metagenome; dual media filters at the Ann Arbor, Michigan drinking water treatment plant 39089 39013 - Asp GTC [ENA] ¢þ
>WENV170783460 MAAC01017060 [MAAC] seawater metagenome; sample BD02T64 sea water enriched with oil for 64 days 1281 1205 - Asp GTC [ENA] ¢þ
>WENV170783834 MAAC01019213 [MAAC] seawater metagenome; sample BD02T64 sea water enriched with oil for 64 days 473854 473778 - Asp GTC [ENA] ¢þ
>WENV170791717 MDSV01087664 [MDSV] marine metagenome; seawater 1965 1889 - Asp GTC [ENA] ¢þ
>WENV170793192 MDSV01111929 [MDSV] marine metagenome; seawater 5200 5124 - Asp GTC [ENA] ¢þ
>WENV170815406 MDSX01009536 [MDSX] marine metagenome; seawater 3454 3530 + Asp GTC [ENA] ¢þ
>WENV170883754 MDTC01171496 [MDTC] marine metagenome; seawater 1328 1252 - Asp GTC [ENA] ¢þ
>WENV170921890 MDTG01021967 [MDTG] marine metagenome; seawater 33055 32979 - Asp GTC [ENA] ¢þ
>WENV170927760 MDTG01122453 [MDTG] marine metagenome; seawater 3044 3120 + Asp GTC [ENA] ¢þ
>WENV170942388 MDTG01377132 [MDTG] marine metagenome; seawater 34726 34650 - Asp GTC [ENA] ¢þ
>WENV170949656 MEHZ011441925 [MEHZ] marine metagenome; marine surface water 2457 2533 + Asp GTC [ENA] ¢þ
>WENV170950103 MEHZ011477709 [MEHZ] marine metagenome; marine surface water 75 1 - Asp GTC [ENA] ¢þ
>WENV171002611 NHNJ01100164 [NHNJ] marine metagenome; surface waters at 20 m depth at the end of the Scripps Institution of Oceanography (SIO) pier 572 648 + Asp GTC [ENA] ¢þ
>C181047449 CP020918 Bacteroidota Flavobacterium faecale WV33 [CP020918] 564887 564813 - Asp GTC - ¡û
>C181047450 CP020918 Bacteroidota Flavobacterium faecale WV33 [CP020918] 564607 564533 - Asp GTC - ¡û
>C181063583 CP022380 Bacteroidota Capnocytophaga sp. H4358 [CP022380] 1309113 1309039 - Asp GTC - ¡û
>C181063630 CP022381 Bacteroidota Capnocytophaga sp. H2931 [CP022381] 1265233 1265159 - Asp GTC - ¡û
>C181175917 CP029186 Bacteroidota Flavobacterium album HYN0059 [CP029186] 529655 529581 - Asp GTC - ¡û
>C191083488 CP031964 Bacteroidota Flavobacteriaceae bacterium AU392 [CP031964] 57642 57568 - Asp GTC - ¡û
>WENV000188 AACY020006115 Marine microbial communities from Global Ocean Sampling (GOS) 822 900 + Asp GTC [ENA]
>W1910698769 MEPA01000612 Bacteroidota Bacteroidetes bacterium RIFCSPLOWO2_12_FULL_31_6 [MEPA] 2752 2676 - Asp GTC [ENA] ¡û
>W1910728171 MGWJ01000003 Bacteroidota Flavobacteria bacterium RIFCSPLOWO2_12_FULL_31_7 [MGWJ] 6669 6743 + Asp GTC [ENA] ¡û
>W1910728172 MGWJ01000003 Bacteroidota Flavobacteria bacterium RIFCSPLOWO2_12_FULL_31_7 [MGWJ] 7190 7264 + Asp GTC [ENA] ¡û
>W1910785531 MQUA01000004 Bacteroidota Polaribacter filamentus ATCC 700397 [MQUA] 88323 88397 + Asp GTC [ENA] ¡û
>W1910796613 MSCM01000001 Bacteroidota Polaribacter glomeratus ATCC 43844 [MSCM] 2236510 2236436 - Asp GTC [ENA] ¡û
>W1911139363 NOXV01000214 Bacteroidota Flavobacterium cyanobacteriorum TH021 [NOXV] 6207 6281 + Asp GTC [ENA] ¡û
>W1911239259 NSDI01000010 Bacteroidota Capnocytophaga canis 17-158 [NSDI] 81774 81700 - Asp GTC [ENA] ¡û
>W1911686179 QKWS01000001 Bacteroidota Meridianimaribacter sp. CL38 [QKWS] 653115 653041 - Asp GTC [ENA] ¡û
>W1911765429 QXCW01000002 Bacteroidota Flavobacteriaceae bacterium MAR_2010_72 MAR_2010_72 Mar_2010_72 [QXCW] 318410 318484 + Asp GTC [ENA] ¡û
>SRA1003116 SRR002326.210811 The Glacier Ice Metagenome Of The Northern Schneeferner (SRP000240) 43 117 + Asp GTC [SRA]
>SRA1038843 SRR035090.378975 454 Sequencing (SRP001811) 145 71 - Asp GTC [SRA]
>W1510076320 CDOH01000129 Bacteroidota Capnocytophaga canis CcD95 [CDOH] 11691 11767 + Asp GTC [ENA] ¡û
>W1510076346 CDOI01000134 Bacteroidota Capnocytophaga canis CcD38 [CDOI] 22129 22053 - Asp GTC [ENA] ¡û
>W1510076448 CDOL01000013 Bacteroidota Capnocytophaga canis CcD93 [CDOL] 11666 11742 + Asp GTC [ENA] ¡û
>W1511592698 LBIO01000062 Bacteroidota Mangrovimonas sp. TPBH4 [LBIO] 146015 146091 + Asp GTC [ENA] ¡û
>W1511592708 LBIP01000013 Bacteroidota Mangrovimonas xylaniphaga ST2L12 [LBIP] 1960087 1960163 + Asp GTC [ENA] ¡û
>W121062926 AJJU01000003 Bacteroidota Imtechella halotolerans K1 [AJJU] 92512 92436 - Asp GTC [ENA] ¡û
>W1610535094 JRLX01000010 Bacteroidota Flavobacterium rivuli WB 3.3-2 = DSM 21788 [JRLX] 19737 19663 - Asp GTC [ENA] ¡û
>W1610535095 JRLX01000014 Bacteroidota Flavobacterium rivuli WB 3.3-2 = DSM 21788 [JRLX] 13532 13608 + Asp GTC [ENA] ¡û
>W1610946561 LUYZ01000002 Bacteroidota Bacteroidales bacterium Bact_08 [LUYZ] 862 786 - Asp GTC [ENA] ¡û
>W1610946572 LUYZ01000077 Bacteroidota Bacteroidales bacterium Bact_08 [LUYZ] 3306 3382 + Asp GTC [ENA] ¡û
>W1710533470 FNRD01000002 Bacteroidota Flavobacterium gillisiae [FNRD] 1765 1691 - Asp GTC [ENA] ¡û
>W1710533471 FNRD01000002 Bacteroidota Flavobacterium gillisiae [FNRD] 1171 1095 - Asp GTC [ENA] ¡û
>W1710541075 FNYA01000008 Bacteroidota Flavobacterium terrigena [FNYA] 68111 68187 + Asp GTC [ENA] ¡û
>W1710555828 FOJT01000004 Bacteroidota Flavobacterium swingsii [FOJT] 286489 286565 + Asp GTC [ENA] ¡û
>W1710574129 FOYA01000011 Bacteroidota Flavobacterium akiainvivens [FOYA] 57414 57490 + Asp GTC [ENA] ¡û
>W1710637330 JRLX01000010 Bacteroidota Flavobacterium rivuli WB 3.3-2 = DSM 21788 [JRLX] 19737 19663 - Asp GTC [ENA] ¡û
>W1710637331 JRLX01000014 Bacteroidota Flavobacterium rivuli WB 3.3-2 = DSM 21788 [JRLX] 13532 13608 + Asp GTC [ENA] ¡û
Select
Sequence ID Genome ID
(or Accession No.)
Phylum/Class
(Sample source for ENV)
Species Start End Direction AA Anticodon Genome/Seq. Info. Decision
Download Sequence Representative sequence of each cluster
View ClustalW result

BACK