scholarly journals The archaic chaperone–usher pathways may depend on donor strand exchange for intersubunit interactions

Microbiology ◽  
2014 ◽  
Vol 160 (10) ◽  
pp. 2200-2207 ◽  
Author(s):  
Miaomiao Wu ◽  
Shihui Xu ◽  
Wei Zhu ◽  
Xiaohua Mao
Keyword(s):  
Critical Role ◽  
Strand Exchange ◽  
Single Amino Acid ◽  
Spore Coat ◽  
Coat Proteins ◽  
Subunit Interactions ◽  
System A ◽  
Spore Coat Proteins ◽  
Donor Strand Exchange ◽  
Intersubunit Interactions

Subunit–subunit interactions of the classical and alternate chaperone–usher (CU) systems have been shown to proceed through a donor strand exchange (DSE) mechanism. However, it is not known whether DSE is required for intersubunit interactions in the archaic CU system. We have previously shown that the Myxococcus xanthus Mcu system, a member of the archaic CU family that functions in spore coat formation, is likely to use the principle of donor strand complementation to medicate chaperone–subunit interactions analogous to the classical CU pathway. Here we describe the results of studies on Mcu subunit–subunit interactions. We constructed a series of N-terminal-deleted, single amino acid-mutated and donor strand-complemented Mcu subunits, and characterized their abilities to participate in subunit–subunit interactions. It appears that certain residues in both the N and C termini of McuA, a subunit of the Mcu system, play a critical role in intersubunit interactions and these interactions may involve the general principle of DSE of the classical and alternate CU systems. In addition, the specificity of the M. xanthus CU system for Mcu subunits over other spore coat proteins is demonstrated.

scholarly journals SpoVID Guides SafA to the Spore Coat inBacillus subtilis

2001 ◽  
Vol 183 (10) ◽  
pp. 3041-3049 ◽  
Author(s):  
Amanda J. Ozin ◽  
Craig S. Samford ◽  
Adriano O. Henriques ◽  
Charles P. Moran
Keyword(s):  
Direct Interaction ◽  
Spore Coat ◽  
Coat Proteins ◽  
Yeast Two Hybrid System ◽  
Spore Coat Proteins ◽  
Basement Layer ◽  
Two Hybrid ◽  
Spore Coat Protein

ABSTRACT Bacteria assemble complex structures by targeting proteins to specific subcellular locations. The protein coat that encasesBacillus subtilis spores is an example of a structure that requires coordinated targeting and assembly of more than 24 polypeptides. The earliest stages of coat assembly require the action of three morphogenetic proteins: SpoIVA, CotE, and SpoVID. In the first steps, a basement layer of SpoIVA forms around the surface of the forespore, guiding the subsequent positioning of a ring of CotE protein about 75 nm from the forespore surface. SpoVID localizes near the forespore membrane where it functions to maintain the integrity of the CotE ring and to anchor the nascent coat to the underlying spore structures. However, it is not known which spore coat proteins interact directly with SpoVID. In this study we examined the interaction between SpoVID and another spore coat protein, SafA, in vivo using the yeast two-hybrid system and in vitro. We found evidence that SpoVID and SafA directly interact and that SafA interacts with itself. Immunofluorescence microscopy showed that SafA localized around the forespore early during coat assembly and that this localization of SafA was dependent on SpoVID. Moreover, targeting of SafA to the forespore was also dependent on SpoIVA, as was targeting of SpoVID to the forespore. We suggest that the localization of SafA to the spore coat requires direct interaction with SpoVID.

Cloning and expression of a cDNA that comprises part of the gene coding for a spore coat protein of Dictyostelium discoideum

1984 ◽  
Vol 4 (11) ◽  
pp. 2273-2278
Author(s):  
B C Dowds ◽  
W F Loomis
Keyword(s):  
Dictyostelium Discoideum ◽  
Cdna Clone ◽  
Single Gene ◽  
Polyclonal Antiserum ◽  
Cloning And Expression ◽  
Spore Coat ◽  
Coat Proteins ◽  
Developmentally Regulated ◽  
Gene Coding ◽  
Spore Coat Proteins

The three major spore coat proteins of Dictyostelium discoideum are developmentally regulated, cell-type-specific proteins. They are packaged in prespore vesicles and then secreted to form the outer layer of spore coats. We have isolated a cDNA clone from the gene coding for one of these proteins, SP96, a glycoprotein of 96,000 daltons. We screened the cDNA bank by the method of hybrid select translation followed by immunoprecipitation of the translation products with SP96-specific polyclonal antiserum. We found that the gene was first transcribed into stable mRNA a few hours before the time of detection of SP96 synthesis and that the mRNA, like the protein, accumulated specifically in prespore cells and spores. SP96 constituted the same proportion of newly synthesized protein as the proportion of its message in polyadenylated RNA. SP96 appeared to be encoded by a single gene as judged by Southern blot analysis of digested genomic DNA hybridized to the cDNA clone.

scholarly journals Synthesis and Deposition of Spore Coat Proteins during Sporulation ofBacillus megaterium

1985 ◽  
Vol 29 (12) ◽  
pp. 1151-1162 ◽  
Author(s):  
Masayoshi Imagawa ◽  
Yuichi Oku ◽  
Hussein I. El-Belbasi ◽  
Mie Teraoka ◽  
Tsutomu Nishihara ◽  
...  
Keyword(s):  
Spore Coat ◽  
Coat Proteins ◽  
Spore Coat Proteins

scholarly journals The yabG gene of Bacillus subtilis encodes a sporulation specific protease which is involved in the processing of several spore coat proteins

2000 ◽  
Vol 192 (1) ◽  
pp. 33-38 ◽  
Author(s):  
Hiromu Takamatsu ◽  
Atsuo Imamura ◽  
Takeko Kodama ◽  
Kei Asai ◽  
Naotake Ogasawara ◽  
...  
Keyword(s):  
Bacillus Subtilis ◽  
Spore Coat ◽  
Coat Proteins ◽  
Specific Protease ◽  
Spore Coat Proteins

Phosphorylation of spore coat proteins of Dictyostelium discoideum

1983 ◽  
Vol 61 (9) ◽  
pp. 996-1001 ◽  
Author(s):  
Teshome Akalehiywot ◽  
Chi-Hung Siu
Keyword(s):  
Electrophoretic Mobility ◽  
Dictyostelium Discoideum ◽  
Cellular Proteins ◽  
Developmental Cycle ◽  
Spore Coat ◽  
Coat Proteins ◽  
Phosphoamino Acid ◽  
Molecular Weights ◽  
Phosphorylated Proteins ◽  
Spore Coat Proteins

Phosphorylation of cellular proteins was studied during development of Dictyostelium discoideum. In the second half of the developmental cycle, two heavily phosphorylated proteins were observed together with a limited number of minor phosphorylated proteins. The electrophoretic mobility of these two phosphoproteins corresponded to two of the major spore coat glycoproteins, with apparent molecular weights of 103 000 and 80 000. They were found to be externalized and associated with the spore coat during spore formation. Phosphoserine was the predominant phosphoamino acid in both cases. These two phosphoproteins thus serve as excellent markers for the differentiation of prespore cells in D. discoideum.

scholarly journals Localization of the Cortex Lytic Enzyme CwlJ in Spores of Bacillus subtilis

2002 ◽  
Vol 184 (4) ◽  
pp. 1219-1224 ◽  
Author(s):  
Irina Bagyan ◽  
Peter Setlow
Keyword(s):  
Bacillus Subtilis ◽  
Spore Germination ◽  
Dipicolinic Acid ◽  
High Salt ◽  
Lytic Enzyme ◽  
Spore Coat ◽  
Coat Proteins ◽  
His Tag ◽  
Spore Coat Proteins ◽  
Triton X

ABSTRACT The enzyme CwlJ is involved in the depolymerization of cortex peptidoglycan during germination of spores of Bacillus subtilis. CwlJ with a C-terminal His tag was functional and was extracted from spores by procedures that remove spore coat proteins. However, this CwlJ was not extracted from disrupted spores by dilute buffer, high salt concentrations, Triton X-100, Ca2+-dipicolinic acid, dithiothreitol, or peptidoglycan digestion, disappeared during spore germination, and was not present in cotE spores in which the spore coat is aberrant. These findings indicate the following: (i) the reason decoated and cotE spores germinate poorly with dipicolinic acid is the absence of CwlJ from these spores; and (ii) CwlJ is located in the spore coat, presumably tightly associated with one or more other coat proteins.

scholarly journals Phosphorylation of spore coat proteins by a family of atypical protein kinases

2016 ◽  
Vol 113 (25) ◽  
pp. E3482-E3491 ◽  
Author(s):  
Kim B. Nguyen ◽  
Anju Sreelatha ◽  
Eric S. Durrant ◽  
Javier Lopez-Garrido ◽  
Anna Muszewska ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Protein Kinases ◽  
Secretory Pathway ◽  
Sequence Similarity ◽  
Life Forms ◽  
Extracellular Proteins ◽  
Spore Coat ◽  
Coat Proteins ◽  
Eukaryotic Species ◽  
Spore Coat Proteins

The modification of proteins by phosphorylation occurs in all life forms and is catalyzed by a large superfamily of enzymes known as protein kinases. We recently discovered a family of secretory pathway kinases that phosphorylate extracellular proteins. One member, family with sequence similarity 20C (Fam20C), is the physiological Golgi casein kinase. While examining distantly related protein sequences, we observed low levels of identity between the spore coat protein H (CotH), and the Fam20C-related secretory pathway kinases. CotH is a component of the spore in many bacterial and eukaryotic species, and is required for efficient germination of spores inBacillus subtilis; however, the mechanism by which CotH affects germination is unclear. Here, we show that CotH is a protein kinase. The crystal structure of CotH reveals an atypical protein kinase-like fold with a unique mode of ATP binding. Examination of the genes neighboringcotHinB. subtilisled us to identify two spore coat proteins, CotB and CotG, as CotH substrates. Furthermore, we show that CotH-dependent phosphorylation of CotB and CotG is required for the efficient germination ofB. subtilisspores. Collectively, our results define a family of atypical protein kinases and reveal an unexpected role for protein phosphorylation in spore biology.

Sign in / Sign up

Export Citation Format

Share Document