Score = 118 (46.6 bits), Expect = 9.3e-07, P = 9.3e-07
Identities = 23/45 (51%), Positives = 31/45 (68%)
Query: 1 MAKLCGEARRLKDKFLSFQISHVLRNLNSEADAQATLAVGLADGE 45
MA+LC +A+ L + F +F I H+ R NSEAD QA A+ LADG+
Sbjct: 243 MAELCKQAKELMNSFKTFDIKHIAREKNSEADKQANSAIFLADGQ 287
Parameters:
V=100
filter=SEG
E=0.001
ctxfactor=1.00
Query ----- As Used ----- ----- Computed ----
Frame MatID Matrix name Lambda K H Lambda K H
+0 0 BLOSUM62 0.320 0.132 0.365 same same same
Q=9,R=2 0.244 0.0300 0.180 n/a n/a n/a
Query
Frame MatID Length Eff.Length E S W T X E2 S2
+0 0 52 52 0.00091 102 3 11 22 0.37 27
29 0.47 26
Statistics:
Database: /share/blast/go-seqdb.fasta
Title: go_20130330-seqdb.fasta
Posted: 5:47:42 AM PDT Apr 1, 2013
Created: 5:47:42 AM PDT Apr 1, 2013
Format: XDF-1
# of letters in database: 169,044,731
# of sequences in database: 368,745
# of database sequences satisfying E: 2
No. of states in DFA: 389 (42 KB)
Total size of DFA: 63 KB (2059 KB)
Time to generate neighborhood: 0.00u 0.00s 0.00t Elapsed: 00:00:00
No. of threads or processors used: 24
Search cpu time: 5.91u 0.15s 6.06t Elapsed: 00:00:00
Total cpu time: 5.91u 0.15s 6.06t Elapsed: 00:00:00
Start: Thu May 9 16:25:55 2013 End: Thu May 9 16:25:55 2013
Score = 43.3 bits (103), Expect = 2e-07
Identities = 16/38 (42%), Positives = 19/38 (50%)
Query: 1 MAKLCGEARRLKDKFLSFQISHVLRNLNSEADAQATLA 38
+A EAR L KF +I + R N EADA A A
Sbjct: 89 LAPYLEEARELLKKFEEVEIKWIPREENKEADALANQA 126
Ribonuclease H (RNase H) is classified into two evolutionarily unrelated families, type 1 (prokaryotic RNase HI, eukaryotic RNase H1 and viral RNase H) and type 2 (prokaryotic RNase HII and HIII, and eukaryotic RNase H2). RNase H is an endonuclease that cleaves the RNA strand of an RNA/DNA hybrid in a sequence non-specific manner. RNase H is involved in DNA replication, repair and transcription. RNase H is widely present in various organisms, including bacteria, archaea and eukaryotes and most prokaryotic and eukaryotic genomes contain multiple RNase H genes. Despite the lack of amino acid sequence homology, Type 1 and type 2 RNase H share a main-chain fold and steric configurations of the four acidic active-site (DEDD) residues and have the same catalytic mechanism and functions in cells. One of the important functions of RNase H is to remove Okazaki fragments during DNA replication. Most archaeal genomes contain only type 2 RNase H (RNase HII); however, a few contain RNase HI as well. Although archaeal RNase HI sequences conserve the DEDD active-site motif, they lack other common features important for catalytic function, such as the basic protrusion region. Archaeal RNase HI homologs are more closely related to retroviral RNase HI than bacterial and eukaryotic type I RNase H in enzymatic properties. Length = 128
Score = 35.2 bits (82), Expect = 1e-04
Identities = 19/38 (50%), Positives = 22/38 (57%)
Query: 1 MAKLCGEARRLKDKFLSFQISHVLRNLNSEADAQATLA 38
+A L E R+L KF S +SHV R N ADA A LA
Sbjct: 48 LAALLREIRKLLKKFDSVSVSHVPRECNRVADALAKLA 85
This domain is found in plants and appears to be part of a retrotransposon. Length = 88
One of the important functions of RNase H is to remove Okazaki fragments during DNA replication. RNase H knockout mice lack mitochondrial DNA replication and die as embryos. The retroviral reverse transcriptase contains an RNase H domain that plays an important role in converting a single stranded retroviral genomic RNA into a dsDNA for integration into host chromosomes. RNase H inhibitors have been explored as an anti-HIV drug target because RNase H inactivation inhibits reverse transcription.
>COG0328 RnhA Ribonuclease HI [DNA replication, recombination, and repair]
>PF00075 RNase_H: RNase H; InterPro: IPR002156 The RNase H domain is responsible for hydrolysis of the RNA portion of RNA x DNA hybrids, and this activity requires the presence of divalent cations (Mg2+ or Mn2+) that bind its active site
This domain is a part of a large family of homologous RNase H enzymes of which the RNase HI protein from Escherichia coli is the best characterised []. Secondary structure predictions for the enzymes from E. coli, yeast, human liver and diverse retroviruses (such as Rous sarcoma virus and the Foamy viruses) supported, in every case, the five beta-strands (1 to 5) and four or five alpha-helices (A, B/C, D, E) that have been identified by crystallography in the RNase H domain of Human immunodeficiency virus 1 (HIV-1) reverse transcriptase and in E. coli RNase H []. Reverse transcriptase (RT) is a modular enzyme carrying polymerase and ribonuclease H (RNase H) activities in separable domains. Reverse transcriptase (RT) converts the single-stranded RNA genome of a retrovirus into a double-stranded DNA copy for integration into the host genome. This process requires ribonuclease H as well as RNA- and DNA-directed DNA polymerase activities. Retroviral RNase H is synthesised as part of the POL polyprotein that contains; an aspartyl protease, a reverse transcriptase, RNase H and integrase. POL polyprotein undergoes specific enzymatic cleavage to yield the mature proteins. Bacterial RNase H 3.1.26.4 from EC catalyses endonucleolytic cleavage to 5'-phosphomonoester acting on RNA-DNA hybrids. The 3D structure of the RNase H domain from diverse bacteria and retroviruses has been solved [, , ]. All have four beta strands and four to five alpha helices. The E. coli RNase H1 protein binds a single Mg2+ ion cofactor in the active site of the enzyme. The divalent cation is bound by the carboxyl groups of four acidic residues, Asp-10, Glu-48, Asp-70, and Asp-134 []. The first three acidic residues are highly conserved in all bacterial and retroviral RNase H sequences. ; GO: 0003676 nucleic acid binding, 0004523 ribonuclease H activity; PDB: 3LP3_B 2KW4_A 3P1G_A 1RIL_A 2RPI_A 4EQJ_G 4EP2_B 3OTY_P 3U3G_D 2ZQB_D ....
class: Alpha and beta proteins (a/b)
fold: Ribonuclease H-like motif
superfamily: Ribonuclease H-like
family: Ribonuclease H
domain: HIV RNase H (Domain of reverse transcriptase)
species: Human immunodeficiency virus type 2 [TaxId: 11709]
class: Alpha and beta proteins (a/b)
fold: Ribonuclease H-like motif
superfamily: Ribonuclease H-like
family: Ribonuclease H
domain: HIV RNase H (Domain of reverse transcriptase)
species: Human immunodeficiency virus type 1 [TaxId: 11676]
